From 8befc66519eda9668eb74067805492da9aa817f3 Mon Sep 17 00:00:00 2001
From: Jim Graham <flar@google.com>
Date: Tue, 17 Dec 2019 16:32:58 -0800
Subject: [PATCH 1/4] Update formatting in web_ui scene bulder to match flutter
 style.

---
 .../lib/src/engine/surface/scene_builder.dart | 54 ++++++++++++-------
 lib/web_ui/lib/src/ui/compositing.dart        | 50 ++++++++++-------
 2 files changed, 65 insertions(+), 39 deletions(-)

diff --git a/lib/web_ui/lib/src/engine/surface/scene_builder.dart b/lib/web_ui/lib/src/engine/surface/scene_builder.dart
index b29953a30f3c5..990b8f3fcb1a8 100644
--- a/lib/web_ui/lib/src/engine/surface/scene_builder.dart
+++ b/lib/web_ui/lib/src/engine/surface/scene_builder.dart
@@ -65,8 +65,9 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.OffsetEngineLayer pushOffset(double dx, double dy,
-      {ui.OffsetEngineLayer oldLayer}) {
+  ui.OffsetEngineLayer pushOffset(double dx, double dy, {
+    ui.OffsetEngineLayer oldLayer,
+  }) {
     return _pushSurface(PersistedOffset(oldLayer, dx, dy));
   }
 
@@ -76,8 +77,9 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.TransformEngineLayer pushTransform(Float64List matrix4,
-      {ui.TransformEngineLayer oldLayer}) {
+  ui.TransformEngineLayer pushTransform(Float64List matrix4, {
+    ui.TransformEngineLayer oldLayer,
+  }) {
     if (matrix4 == null) {
       throw ArgumentError('"matrix4" argument cannot be null');
     }
@@ -94,8 +96,10 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
   @override
-  ui.ClipRectEngineLayer pushClipRect(ui.Rect rect,
-      {ui.Clip clipBehavior = ui.Clip.antiAlias, ui.ClipRectEngineLayer oldLayer}) {
+  ui.ClipRectEngineLayer pushClipRect(ui.Rect rect, {
+    ui.Clip clipBehavior = ui.Clip.antiAlias,
+    ui.ClipRectEngineLayer oldLayer,
+  }) {
     assert(clipBehavior != null);
     assert(clipBehavior != ui.Clip.none);
     return _pushSurface(PersistedClipRect(oldLayer, rect));
@@ -107,10 +111,11 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ClipRRectEngineLayer pushClipRRect(ui.RRect rrect,
-      {ui.Clip clipBehavior, ui.ClipRRectEngineLayer oldLayer}) {
-    return _pushSurface(
-        PersistedClipRRect(oldLayer, rrect, clipBehavior));
+  ui.ClipRRectEngineLayer pushClipRRect(ui.RRect rrect, {
+    ui.Clip clipBehavior,
+    ui.ClipRRectEngineLayer oldLayer,
+  }) {
+    return _pushSurface(PersistedClipRRect(oldLayer, rrect, clipBehavior));
   }
 
   /// Pushes a path clip operation onto the operation stack.
@@ -119,8 +124,10 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ClipPathEngineLayer pushClipPath(ui.Path path,
-      {ui.Clip clipBehavior = ui.Clip.antiAlias, ui.ClipPathEngineLayer oldLayer}) {
+  ui.ClipPathEngineLayer pushClipPath(ui.Path path, {
+    ui.Clip clipBehavior = ui.Clip.antiAlias,
+    ui.ClipPathEngineLayer oldLayer,
+  }) {
     assert(clipBehavior != null);
     assert(clipBehavior != ui.Clip.none);
     return _pushSurface(PersistedClipPath(oldLayer, path, clipBehavior));
@@ -135,8 +142,10 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.OpacityEngineLayer pushOpacity(int alpha,
-      {ui.Offset offset = ui.Offset.zero, ui.OpacityEngineLayer oldLayer}) {
+  ui.OpacityEngineLayer pushOpacity(int alpha, {
+    ui.Offset offset = ui.Offset.zero,
+    ui.OpacityEngineLayer oldLayer,
+  }) {
     return _pushSurface(PersistedOpacity(oldLayer, alpha, offset));
   }
 
@@ -151,8 +160,9 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ColorFilterEngineLayer pushColorFilter(ui.ColorFilter filter,
-      {ui.ColorFilterEngineLayer oldLayer}) {
+  ui.ColorFilterEngineLayer pushColorFilter(ui.ColorFilter filter, {
+    ui.ColorFilterEngineLayer oldLayer,
+  }) {
     assert(filter != null);
     throw UnimplementedError();
   }
@@ -164,8 +174,9 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.BackdropFilterEngineLayer pushBackdropFilter(ui.ImageFilter filter,
-      {ui.BackdropFilterEngineLayer oldLayer}) {
+  ui.BackdropFilterEngineLayer pushBackdropFilter(ui.ImageFilter filter, {
+    ui.BackdropFilterEngineLayer oldLayer,
+  }) {
     return _pushSurface(PersistedBackdropFilter(oldLayer, filter));
   }
 
@@ -177,8 +188,11 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// See [pop] for details about the operation stack.
   @override
   ui.ShaderMaskEngineLayer pushShaderMask(
-      ui.Shader shader, ui.Rect maskRect, ui.BlendMode blendMode,
-      {ui.ShaderMaskEngineLayer oldLayer}) {
+    ui.Shader shader,
+    ui.Rect maskRect,
+    ui.BlendMode blendMode, {
+    ui.ShaderMaskEngineLayer oldLayer,
+  }) {
     throw UnimplementedError();
   }
 
diff --git a/lib/web_ui/lib/src/ui/compositing.dart b/lib/web_ui/lib/src/ui/compositing.dart
index 96d83d52fd906..af4f39a90e856 100644
--- a/lib/web_ui/lib/src/ui/compositing.dart
+++ b/lib/web_ui/lib/src/ui/compositing.dart
@@ -117,16 +117,18 @@ abstract class SceneBuilder {
   /// This is equivalent to [pushTransform] with a matrix with only translation.
   ///
   /// See [pop] for details about the operation stack.
-  OffsetEngineLayer pushOffset(double dx, double dy,
-      {OffsetEngineLayer oldLayer});
+  OffsetEngineLayer pushOffset(double dx, double dy, {
+    OffsetEngineLayer oldLayer,
+  });
 
   /// Pushes a transform operation onto the operation stack.
   ///
   /// The objects are transformed by the given matrix before rasterization.
   ///
   /// See [pop] for details about the operation stack.
-  TransformEngineLayer pushTransform(Float64List matrix4,
-      {TransformEngineLayer oldLayer});
+  TransformEngineLayer pushTransform(Float64List matrix4, {
+    TransformEngineLayer oldLayer,
+  });
 
   /// Pushes a rectangular clip operation onto the operation stack.
   ///
@@ -134,24 +136,30 @@ abstract class SceneBuilder {
   ///
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
-  ClipRectEngineLayer pushClipRect(Rect rect,
-      {Clip clipBehavior = Clip.antiAlias, ClipRectEngineLayer oldLayer});
+  ClipRectEngineLayer pushClipRect(Rect rect, {
+    Clip clipBehavior = Clip.antiAlias,
+    ClipRectEngineLayer oldLayer,
+  });
 
   /// Pushes a rounded-rectangular clip operation onto the operation stack.
   ///
   /// Rasterization outside the given rounded rectangle is discarded.
   ///
   /// See [pop] for details about the operation stack.
-  ClipRRectEngineLayer pushClipRRect(RRect rrect,
-      {Clip clipBehavior, ClipRRectEngineLayer oldLayer});
+  ClipRRectEngineLayer pushClipRRect(RRect rrect, {
+    Clip clipBehavior,
+    ClipRRectEngineLayer oldLayer,
+  });
 
   /// Pushes a path clip operation onto the operation stack.
   ///
   /// Rasterization outside the given path is discarded.
   ///
   /// See [pop] for details about the operation stack.
-  ClipPathEngineLayer pushClipPath(Path path,
-      {Clip clipBehavior = Clip.antiAlias, ClipPathEngineLayer oldLayer});
+  ClipPathEngineLayer pushClipPath(Path path, {
+    Clip clipBehavior = Clip.antiAlias,
+    ClipPathEngineLayer oldLayer,
+  });
 
   /// Pushes an opacity operation onto the operation stack.
   ///
@@ -161,8 +169,10 @@ abstract class SceneBuilder {
   /// opacity).
   ///
   /// See [pop] for details about the operation stack.
-  OpacityEngineLayer pushOpacity(int alpha,
-      {Offset offset = Offset.zero, OpacityEngineLayer oldLayer});
+  OpacityEngineLayer pushOpacity(int alpha, {
+    Offset offset = Offset.zero,
+    OpacityEngineLayer oldLayer,
+  });
 
   /// Pushes a color filter operation onto the operation stack.
   ///
@@ -174,8 +184,9 @@ abstract class SceneBuilder {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  ColorFilterEngineLayer pushColorFilter(ColorFilter filter,
-      {ColorFilterEngineLayer oldLayer});
+  ColorFilterEngineLayer pushColorFilter(ColorFilter filter, {
+    ColorFilterEngineLayer oldLayer,
+  });
 
   /// Pushes a backdrop filter operation onto the operation stack.
   ///
@@ -183,8 +194,9 @@ abstract class SceneBuilder {
   /// rasterizing the given objects.
   ///
   /// See [pop] for details about the operation stack.
-  BackdropFilterEngineLayer pushBackdropFilter(ImageFilter filter,
-      {BackdropFilterEngineLayer oldLayer});
+  BackdropFilterEngineLayer pushBackdropFilter(ImageFilter filter, {
+    BackdropFilterEngineLayer oldLayer,
+  });
 
   /// Pushes a shader mask operation onto the operation stack.
   ///
@@ -192,9 +204,9 @@ abstract class SceneBuilder {
   /// rectangle using the given blend mode.
   ///
   /// See [pop] for details about the operation stack.
-  ShaderMaskEngineLayer pushShaderMask(
-      Shader shader, Rect maskRect, BlendMode blendMode,
-      {ShaderMaskEngineLayer oldLayer});
+  ShaderMaskEngineLayer pushShaderMask(Shader shader, Rect maskRect, BlendMode blendMode, {
+    ShaderMaskEngineLayer oldLayer,
+  });
 
   /// Pushes a physical layer operation for an arbitrary shape onto the
   /// operation stack.

From dbb725a4607c7e4dacc4a0abc098df81c8ee2d9f Mon Sep 17 00:00:00 2001
From: Jim Graham <flar@google.com>
Date: Thu, 19 Dec 2019 10:24:49 -0800
Subject: [PATCH 2/4] Run dartfmt on all SceneBuilder variants.

---
 lib/ui/compositing.dart                       | 292 +++++++++++-------
 .../compositor/layer_scene_builder.dart       | 107 ++++---
 .../lib/src/engine/surface/scene_builder.dart |  98 +++---
 lib/web_ui/lib/src/ui/compositing.dart        |  86 ++++--
 4 files changed, 372 insertions(+), 211 deletions(-)

diff --git a/lib/ui/compositing.dart b/lib/ui/compositing.dart
index fc1b368bf4f82..4025754ef266d 100644
--- a/lib/ui/compositing.dart
+++ b/lib/ui/compositing.dart
@@ -19,15 +19,11 @@ class Scene extends NativeFieldWrapperClass2 {
   @pragma('vm:entry-point')
   Scene._();
 
-
   /// Creates a raster image representation of the current state of the scene.
   /// This is a slow operation that is performed on a background thread.
   Future<Image> toImage(int width, int height) {
-    if (width <= 0 || height <= 0)
-      throw Exception('Invalid image dimensions.');
-    return _futurize(
-      (_Callback<Image> callback) => _toImage(width, height, callback)
-    );
+    if (width <= 0 || height <= 0) throw Exception('Invalid image dimensions.');
+    return _futurize((_Callback<Image> callback) => _toImage(width, height, callback));
   }
 
   String _toImage(int width, int height, _Callback<Image> callback) native 'Scene_toImage';
@@ -64,13 +60,12 @@ abstract class _EngineLayerWrapper implements EngineLayer {
 
   bool _debugCheckNotUsedAsOldLayer() {
     assert(
-      !_debugWasUsedAsOldLayer,
-      'Layer $runtimeType was previously used as oldLayer.\n'
-      'Once a layer is used as oldLayer, it may not be used again. Instead, '
-      'after calling one of the SceneBuilder.push* methods and passing an oldLayer '
-      'to it, use the layer returned by the method as oldLayer in subsequent '
-      'frames.'
-    );
+        !_debugWasUsedAsOldLayer,
+        'Layer $runtimeType was previously used as oldLayer.\n'
+        'Once a layer is used as oldLayer, it may not be used again. Instead, '
+        'after calling one of the SceneBuilder.push* methods and passing an oldLayer '
+        'to it, use the layer returned by the method as oldLayer in subsequent '
+        'frames.');
     return true;
   }
 }
@@ -179,7 +174,9 @@ class PhysicalShapeEngineLayer extends _EngineLayerWrapper {
 class SceneBuilder extends NativeFieldWrapperClass2 {
   /// Creates an empty [SceneBuilder] object.
   @pragma('vm:entry-point')
-  SceneBuilder() { _constructor(); }
+  SceneBuilder() {
+    _constructor();
+  }
   void _constructor() native 'SceneBuilder_constructor';
 
   // Layers used in this scene.
@@ -196,11 +193,10 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
       }
 
       assert(
-        !_usedLayers.containsKey(layer),
-        'Layer ${layer.runtimeType} already used.\n'
-        'The layer is already being used as ${_usedLayers[layer]} in this scene.\n'
-        'A layer may only be used once in a given scene.'
-      );
+          !_usedLayers.containsKey(layer),
+          'Layer ${layer.runtimeType} already used.\n'
+          'The layer is already being used as ${_usedLayers[layer]} in this scene.\n'
+          'A layer may only be used once in a given scene.');
 
       _usedLayers[layer] = usage;
       return true;
@@ -267,13 +263,17 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@endtemplate}
   ///
   /// See [pop] for details about the operation stack.
-  TransformEngineLayer pushTransform(Float64List matrix4, { TransformEngineLayer oldLayer }) {
+  TransformEngineLayer pushTransform(
+    Float64List matrix4, {
+    TransformEngineLayer oldLayer,
+  }) {
     assert(_matrix4IsValid(matrix4));
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushTransform'));
     final TransformEngineLayer layer = TransformEngineLayer._(_pushTransform(matrix4));
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushTransform(Float64List matrix4) native 'SceneBuilder_pushTransform';
 
   /// Pushes an offset operation onto the operation stack.
@@ -285,12 +285,17 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  OffsetEngineLayer pushOffset(double dx, double dy, { OffsetEngineLayer oldLayer }) {
+  OffsetEngineLayer pushOffset(
+    double dx,
+    double dy, {
+    OffsetEngineLayer oldLayer,
+  }) {
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushOffset'));
     final OffsetEngineLayer layer = OffsetEngineLayer._(_pushOffset(dx, dy));
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushOffset(double dx, double dy) native 'SceneBuilder_pushOffset';
 
   /// Pushes a rectangular clip operation onto the operation stack.
@@ -303,19 +308,22 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   ///
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
-  ClipRectEngineLayer pushClipRect(Rect rect, {Clip clipBehavior = Clip.antiAlias, ClipRectEngineLayer oldLayer }) {
+  ClipRectEngineLayer pushClipRect(
+    Rect rect, {
+    Clip clipBehavior = Clip.antiAlias,
+    ClipRectEngineLayer oldLayer,
+  }) {
     assert(clipBehavior != null);
     assert(clipBehavior != Clip.none);
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushClipRect'));
-    final ClipRectEngineLayer layer = ClipRectEngineLayer._(_pushClipRect(rect.left, rect.right, rect.top, rect.bottom, clipBehavior.index));
+    final ClipRectEngineLayer layer = ClipRectEngineLayer._(
+        _pushClipRect(rect.left, rect.right, rect.top, rect.bottom, clipBehavior.index));
     assert(_debugPushLayer(layer));
     return layer;
   }
-  EngineLayer _pushClipRect(double left,
-                            double right,
-                            double top,
-                            double bottom,
-                            int clipBehavior) native 'SceneBuilder_pushClipRect';
+
+  EngineLayer _pushClipRect(double left, double right, double top, double bottom, int clipBehavior)
+      native 'SceneBuilder_pushClipRect';
 
   /// Pushes a rounded-rectangular clip operation onto the operation stack.
   ///
@@ -327,15 +335,22 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   ///
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
-  ClipRRectEngineLayer pushClipRRect(RRect rrect, {Clip clipBehavior = Clip.antiAlias, ClipRRectEngineLayer oldLayer}) {
+  ClipRRectEngineLayer pushClipRRect(
+    RRect rrect, {
+    Clip clipBehavior = Clip.antiAlias,
+    ClipRRectEngineLayer oldLayer,
+  }) {
     assert(clipBehavior != null);
     assert(clipBehavior != Clip.none);
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushClipRRect'));
-    final ClipRRectEngineLayer layer = ClipRRectEngineLayer._(_pushClipRRect(rrect._value32, clipBehavior.index));
+    final ClipRRectEngineLayer layer =
+        ClipRRectEngineLayer._(_pushClipRRect(rrect._value32, clipBehavior.index));
     assert(_debugPushLayer(layer));
     return layer;
   }
-  EngineLayer _pushClipRRect(Float32List rrect, int clipBehavior) native 'SceneBuilder_pushClipRRect';
+
+  EngineLayer _pushClipRRect(Float32List rrect, int clipBehavior)
+      native 'SceneBuilder_pushClipRRect';
 
   /// Pushes a path clip operation onto the operation stack.
   ///
@@ -347,14 +362,20 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   ///
   /// See [pop] for details about the operation stack. See [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
-  ClipPathEngineLayer pushClipPath(Path path, {Clip clipBehavior = Clip.antiAlias, ClipPathEngineLayer oldLayer}) {
+  ClipPathEngineLayer pushClipPath(
+    Path path, {
+    Clip clipBehavior = Clip.antiAlias,
+    ClipPathEngineLayer oldLayer,
+  }) {
     assert(clipBehavior != null);
     assert(clipBehavior != Clip.none);
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushClipPath'));
-    final ClipPathEngineLayer layer = ClipPathEngineLayer._(_pushClipPath(path, clipBehavior.index));
+    final ClipPathEngineLayer layer =
+        ClipPathEngineLayer._(_pushClipPath(path, clipBehavior.index));
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushClipPath(Path path, int clipBehavior) native 'SceneBuilder_pushClipPath';
 
   /// Pushes an opacity operation onto the operation stack.
@@ -369,12 +390,18 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  OpacityEngineLayer pushOpacity(int alpha, {Offset offset = Offset.zero, OpacityEngineLayer oldLayer}) {
+  OpacityEngineLayer pushOpacity(
+    int alpha, {
+    Offset offset = Offset.zero,
+    OpacityEngineLayer oldLayer,
+  }) {
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushOpacity'));
-    final OpacityEngineLayer layer = OpacityEngineLayer._(_pushOpacity(alpha, offset.dx, offset.dy));
+    final OpacityEngineLayer layer =
+        OpacityEngineLayer._(_pushOpacity(alpha, offset.dx, offset.dy));
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushOpacity(int alpha, double dx, double dy) native 'SceneBuilder_pushOpacity';
 
   /// Pushes a color filter operation onto the operation stack.
@@ -387,7 +414,10 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  ColorFilterEngineLayer pushColorFilter(ColorFilter filter, { ColorFilterEngineLayer oldLayer }) {
+  ColorFilterEngineLayer pushColorFilter(
+    ColorFilter filter, {
+    ColorFilterEngineLayer oldLayer,
+  }) {
     assert(filter != null);
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushColorFilter'));
     final _ColorFilter nativeFilter = filter._toNativeColorFilter();
@@ -396,6 +426,7 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushColorFilter(_ColorFilter filter) native 'SceneBuilder_pushColorFilter';
 
   /// Pushes a backdrop filter operation onto the operation stack.
@@ -408,12 +439,17 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  BackdropFilterEngineLayer pushBackdropFilter(ImageFilter filter, { BackdropFilterEngineLayer oldLayer }) {
+  BackdropFilterEngineLayer pushBackdropFilter(
+    ImageFilter filter, {
+    BackdropFilterEngineLayer oldLayer,
+  }) {
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushBackdropFilter'));
-    final BackdropFilterEngineLayer layer = BackdropFilterEngineLayer._(_pushBackdropFilter(filter._toNativeImageFilter()));
+    final BackdropFilterEngineLayer layer =
+        BackdropFilterEngineLayer._(_pushBackdropFilter(filter._toNativeImageFilter()));
     assert(_debugPushLayer(layer));
     return layer;
   }
+
   EngineLayer _pushBackdropFilter(_ImageFilter filter) native 'SceneBuilder_pushBackdropFilter';
 
   /// Pushes a shader mask operation onto the operation stack.
@@ -426,23 +462,26 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  ShaderMaskEngineLayer pushShaderMask(Shader shader, Rect maskRect, BlendMode blendMode, { ShaderMaskEngineLayer oldLayer }) {
+  ShaderMaskEngineLayer pushShaderMask(
+    Shader shader,
+    Rect maskRect,
+    BlendMode blendMode, {
+    ShaderMaskEngineLayer oldLayer,
+  }) {
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushShaderMask'));
-    final ShaderMaskEngineLayer layer = ShaderMaskEngineLayer._(_pushShaderMask(shader,
-                           maskRect.left,
-                           maskRect.right,
-                           maskRect.top,
-                           maskRect.bottom,
-                           blendMode.index));
+    final ShaderMaskEngineLayer layer = ShaderMaskEngineLayer._(_pushShaderMask(
+        shader, maskRect.left, maskRect.right, maskRect.top, maskRect.bottom, blendMode.index));
     assert(_debugPushLayer(layer));
     return layer;
   }
-  EngineLayer _pushShaderMask(Shader shader,
-                              double maskRectLeft,
-                              double maskRectRight,
-                              double maskRectTop,
-                              double maskRectBottom,
-                              int blendMode) native 'SceneBuilder_pushShaderMask';
+
+  EngineLayer _pushShaderMask(
+      Shader shader,
+      double maskRectLeft,
+      double maskRectRight,
+      double maskRectTop,
+      double maskRectBottom,
+      int blendMode) native 'SceneBuilder_pushShaderMask';
 
   /// Pushes a physical layer operation for an arbitrary shape onto the
   /// operation stack.
@@ -461,14 +500,23 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   ///
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   // ignore: deprecated_member_use
-  PhysicalShapeEngineLayer pushPhysicalShape({ Path path, double elevation, Color color, Color shadowColor, Clip clipBehavior = Clip.none, PhysicalShapeEngineLayer oldLayer }) {
+  PhysicalShapeEngineLayer pushPhysicalShape({
+    Path path,
+    double elevation,
+    Color color,
+    Color shadowColor,
+    Clip clipBehavior = Clip.none,
+    PhysicalShapeEngineLayer oldLayer,
+  }) {
     assert(_debugCheckCanBeUsedAsOldLayer(oldLayer, 'pushPhysicalShape'));
-    final PhysicalShapeEngineLayer layer = PhysicalShapeEngineLayer._(_pushPhysicalShape(path, elevation, color.value, shadowColor?.value ?? 0xFF000000, clipBehavior.index));
+    final PhysicalShapeEngineLayer layer = PhysicalShapeEngineLayer._(_pushPhysicalShape(
+        path, elevation, color.value, shadowColor?.value ?? 0xFF000000, clipBehavior.index));
     assert(_debugPushLayer(layer));
     return layer;
   }
-  EngineLayer _pushPhysicalShape(Path path, double elevation, int color, int shadowColor, int clipBehavior) native
-    'SceneBuilder_pushPhysicalShape';
+
+  EngineLayer _pushPhysicalShape(Path path, double elevation, int color, int shadowColor,
+      int clipBehavior) native 'SceneBuilder_pushPhysicalShape';
 
   /// Ends the effect of the most recently pushed operation.
   ///
@@ -482,6 +530,7 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
     }
     _pop();
   }
+
   void _pop() native 'SceneBuilder_pop';
 
   /// Add a retained engine layer subtree from previous frames.
@@ -518,6 +567,7 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
     final _EngineLayerWrapper wrapper = retainedLayer;
     _addRetained(wrapper._nativeLayer);
   }
+
   void _addRetained(EngineLayer retainedLayer) native 'SceneBuilder_addRetained';
 
   /// Adds an object to the scene that displays performance statistics.
@@ -545,30 +595,34 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// for more details.
   // Values above must match constants in //engine/src/sky/compositor/performance_overlay_layer.h
   void addPerformanceOverlay(int enabledOptions, Rect bounds) {
-    _addPerformanceOverlay(enabledOptions,
-                           bounds.left,
-                           bounds.right,
-                           bounds.top,
-                           bounds.bottom);
+    _addPerformanceOverlay(enabledOptions, bounds.left, bounds.right, bounds.top, bounds.bottom);
   }
-  void _addPerformanceOverlay(int enabledOptions,
-                              double left,
-                              double right,
-                              double top,
-                              double bottom) native 'SceneBuilder_addPerformanceOverlay';
+
+  void _addPerformanceOverlay(
+    int enabledOptions,
+    double left,
+    double right,
+    double top,
+    double bottom,
+  ) native 'SceneBuilder_addPerformanceOverlay';
 
   /// Adds a [Picture] to the scene.
   ///
   /// The picture is rasterized at the given offset.
-  void addPicture(Offset offset, Picture picture, { bool isComplexHint = false, bool willChangeHint = false }) {
+  void addPicture(
+    Offset offset,
+    Picture picture, {
+    bool isComplexHint = false,
+    bool willChangeHint = false,
+  }) {
     int hints = 0;
-    if (isComplexHint)
-      hints |= 1;
-    if (willChangeHint)
-      hints |= 2;
+    if (isComplexHint) hints |= 1;
+    if (willChangeHint) hints |= 2;
     _addPicture(offset.dx, offset.dy, picture, hints);
   }
-  void _addPicture(double dx, double dy, Picture picture, int hints) native 'SceneBuilder_addPicture';
+
+  void _addPicture(double dx, double dy, Picture picture, int hints)
+      native 'SceneBuilder_addPicture';
 
   /// Adds a backend texture to the scene.
   ///
@@ -581,11 +635,19 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// previous or new size, to workaround this the framework "freezes" the
   /// texture just before resizing the Android view and un-freezes it when it is
   /// certain that a frame with the new size is ready.
-  void addTexture(int textureId, { Offset offset = Offset.zero, double width = 0.0, double height = 0.0 , bool freeze = false}) {
+  void addTexture(
+    int textureId, {
+    Offset offset = Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    bool freeze = false,
+  }) {
     assert(offset != null, 'Offset argument was null');
     _addTexture(offset.dx, offset.dy, width, height, textureId, freeze);
   }
-  void _addTexture(double dx, double dy, double width, double height, int textureId, bool freeze) native 'SceneBuilder_addTexture';
+
+  void _addTexture(double dx, double dy, double width, double height, int textureId, bool freeze)
+      native 'SceneBuilder_addTexture';
 
   /// Adds a platform view (e.g an iOS UIView) to the scene.
   ///
@@ -603,34 +665,32 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// With a platform view in the scene, Quartz has to composite the two Flutter surfaces and the
   /// embedded UIView. In addition to that, on iOS versions greater than 9, the Flutter frames are
   /// synchronized with the UIView frames adding additional performance overhead.
-  void addPlatformView(int viewId, { Offset offset = Offset.zero, double width = 0.0, double height = 0.0}) {
+  void addPlatformView(
+    int viewId, {
+    Offset offset = Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+  }) {
     assert(offset != null, 'Offset argument was null');
     _addPlatformView(offset.dx, offset.dy, width, height, viewId);
   }
-  void _addPlatformView(double dx, double dy, double width, double height, int viewId) native 'SceneBuilder_addPlatformView';
+
+  void _addPlatformView(double dx, double dy, double width, double height, int viewId)
+      native 'SceneBuilder_addPlatformView';
 
   /// (Fuchsia-only) Adds a scene rendered by another application to the scene
   /// for this application.
-  void addChildScene({
-    Offset offset = Offset.zero,
-    double width = 0.0,
-    double height = 0.0,
-    SceneHost sceneHost,
-    bool hitTestable = true
-  }) {
-    _addChildScene(offset.dx,
-                   offset.dy,
-                   width,
-                   height,
-                   sceneHost,
-                   hitTestable);
+  void addChildScene(
+      {Offset offset = Offset.zero,
+      double width = 0.0,
+      double height = 0.0,
+      SceneHost sceneHost,
+      bool hitTestable = true}) {
+    _addChildScene(offset.dx, offset.dy, width, height, sceneHost, hitTestable);
   }
-  void _addChildScene(double dx,
-                      double dy,
-                      double width,
-                      double height,
-                      SceneHost sceneHost,
-                      bool hitTestable) native 'SceneBuilder_addChildScene';
+
+  void _addChildScene(double dx, double dy, double width, double height, SceneHost sceneHost,
+      bool hitTestable) native 'SceneBuilder_addChildScene';
 
   /// Sets a threshold after which additional debugging information should be recorded.
   ///
@@ -638,7 +698,8 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   /// interested in using this feature, please contact [flutter-dev](https://groups.google.com/forum/#!forum/flutter-dev).
   /// We'll hopefully be able to figure out how to make this feature more useful
   /// to you.
-  void setRasterizerTracingThreshold(int frameInterval) native 'SceneBuilder_setRasterizerTracingThreshold';
+  void setRasterizerTracingThreshold(int frameInterval)
+      native 'SceneBuilder_setRasterizerTracingThreshold';
 
   /// Sets whether the raster cache should checkerboard cached entries. This is
   /// only useful for debugging purposes.
@@ -655,13 +716,15 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
   ///
   /// Currently this interface is difficult to use by end-developers. If you're
   /// interested in using this feature, please contact [flutter-dev](https://groups.google.com/forum/#!forum/flutter-dev).
-  void setCheckerboardRasterCacheImages(bool checkerboard) native 'SceneBuilder_setCheckerboardRasterCacheImages';
+  void setCheckerboardRasterCacheImages(bool checkerboard)
+      native 'SceneBuilder_setCheckerboardRasterCacheImages';
 
   /// Sets whether the compositor should checkerboard layers that are rendered
   /// to offscreen bitmaps.
   ///
   /// This is only useful for debugging purposes.
-  void setCheckerboardOffscreenLayers(bool checkerboard) native 'SceneBuilder_setCheckerboardOffscreenLayers';
+  void setCheckerboardOffscreenLayers(bool checkerboard)
+      native 'SceneBuilder_setCheckerboardOffscreenLayers';
 
   /// Finishes building the scene.
   ///
@@ -688,15 +751,21 @@ class SceneHost extends NativeFieldWrapperClass2 {
   ///
   /// The SceneHost takes ownership of the provided ViewHolder token.
   SceneHost(
-      dynamic viewHolderToken,
-      void Function() viewConnectedCallback,
-      void Function() viewDisconnectedCallback,
-      void Function(bool) viewStateChangedCallback) {
-    _constructor(viewHolderToken, viewConnectedCallback, viewDisconnectedCallback, viewStateChangedCallback);
+    dynamic viewHolderToken,
+    void Function() viewConnectedCallback,
+    void Function() viewDisconnectedCallback,
+    void Function(bool) viewStateChangedCallback,
+  ) {
+    _constructor(
+        viewHolderToken, viewConnectedCallback, viewDisconnectedCallback, viewStateChangedCallback);
   }
 
-  void _constructor(dynamic viewHolderToken, void Function() viewConnectedCallback, void Function() viewDisconnectedCallback, void Function(bool) viewStateChangedCallback)
-      native 'SceneHost_constructor';
+  void _constructor(
+    dynamic viewHolderToken,
+    void Function() viewConnectedCallback,
+    void Function() viewDisconnectedCallback,
+    void Function(bool) viewStateChangedCallbac,
+  ) native 'SceneHost_constructor';
 
   /// Releases the resources associated with the SceneHost.
   ///
@@ -706,11 +775,12 @@ class SceneHost extends NativeFieldWrapperClass2 {
   /// Set properties on the linked scene.  These properties include its bounds,
   /// as well as whether it can be the target of focus events or not.
   void setProperties(
-      double width,
-      double height,
-      double insetTop,
-      double insetRight,
-      double insetBottom,
-      double insetLeft,
-      bool focusable) native 'SceneHost_setProperties';
+    double width,
+    double height,
+    double insetTop,
+    double insetRight,
+    double insetBottom,
+    double insetLeft,
+    bool focusable,
+  ) native 'SceneHost_setProperties';
 }
diff --git a/lib/web_ui/lib/src/engine/compositor/layer_scene_builder.dart b/lib/web_ui/lib/src/engine/compositor/layer_scene_builder.dart
index 9e25b218ca309..ff71900d5fe31 100644
--- a/lib/web_ui/lib/src/engine/compositor/layer_scene_builder.dart
+++ b/lib/web_ui/lib/src/engine/compositor/layer_scene_builder.dart
@@ -26,12 +26,13 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   ContainerLayer currentLayer;
 
   @override
-  void addChildScene(
-      {ui.Offset offset = ui.Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      ui.SceneHost sceneHost,
-      bool hitTestable = true}) {
+  void addChildScene({
+    ui.Offset offset = ui.Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    ui.SceneHost sceneHost,
+    bool hitTestable = true,
+  }) {
     throw UnimplementedError();
   }
 
@@ -42,10 +43,13 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   }
 
   @override
-  void addPicture(ui.Offset offset, ui.Picture picture,
-      {bool isComplexHint = false, bool willChangeHint = false}) {
-    currentLayer
-        .add(PictureLayer(picture, offset, isComplexHint, willChangeHint));
+  void addPicture(
+    ui.Offset offset,
+    ui.Picture picture, {
+    bool isComplexHint = false,
+    bool willChangeHint = false,
+  }) {
+    currentLayer.add(PictureLayer(picture, offset, isComplexHint, willChangeHint));
   }
 
   @override
@@ -57,11 +61,13 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   }
 
   @override
-  void addTexture(int textureId,
-      {ui.Offset offset = ui.Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      bool freeze = false}) {
+  void addTexture(
+    int textureId, {
+    ui.Offset offset = ui.Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    bool freeze = false,
+  }) {
     // TODO(b/128315641): implement addTexture.
   }
 
@@ -90,43 +96,59 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   }
 
   @override
-  ui.BackdropFilterEngineLayer pushBackdropFilter(ui.ImageFilter filter,
-      {ui.EngineLayer oldLayer}) {
+  ui.BackdropFilterEngineLayer pushBackdropFilter(
+    ui.ImageFilter filter, {
+    ui.EngineLayer oldLayer,
+  }) {
     pushLayer(BackdropFilterLayer(filter));
     return null;
   }
 
   @override
-  ui.ClipPathEngineLayer pushClipPath(ui.Path path,
-      {ui.Clip clipBehavior = ui.Clip.antiAlias, ui.EngineLayer oldLayer}) {
+  ui.ClipPathEngineLayer pushClipPath(
+    ui.Path path, {
+    ui.Clip clipBehavior = ui.Clip.antiAlias,
+    ui.EngineLayer oldLayer,
+  }) {
     pushLayer(ClipPathLayer(path, clipBehavior));
     return null;
   }
 
   @override
-  ui.ClipRRectEngineLayer pushClipRRect(ui.RRect rrect,
-      {ui.Clip clipBehavior, ui.EngineLayer oldLayer}) {
+  ui.ClipRRectEngineLayer pushClipRRect(
+    ui.RRect rrect, {
+    ui.Clip clipBehavior,
+    ui.EngineLayer oldLayer,
+  }) {
     pushLayer(ClipRRectLayer(rrect, clipBehavior));
     return null;
   }
 
   @override
-  ui.ClipRectEngineLayer pushClipRect(ui.Rect rect,
-      {ui.Clip clipBehavior = ui.Clip.antiAlias, ui.EngineLayer oldLayer}) {
+  ui.ClipRectEngineLayer pushClipRect(
+    ui.Rect rect, {
+    ui.Clip clipBehavior = ui.Clip.antiAlias,
+    ui.EngineLayer oldLayer,
+  }) {
     pushLayer(ClipRectLayer(rect, clipBehavior));
     return null;
   }
 
   @override
-  ui.ColorFilterEngineLayer pushColorFilter(ui.ColorFilter filter,
-      {ui.ColorFilterEngineLayer oldLayer}) {
+  ui.ColorFilterEngineLayer pushColorFilter(
+    ui.ColorFilter filter, {
+    ui.ColorFilterEngineLayer oldLayer,
+  }) {
     assert(filter != null);
     throw UnimplementedError();
   }
 
   @override
-  ui.OffsetEngineLayer pushOffset(double dx, double dy,
-      {ui.EngineLayer oldLayer}) {
+  ui.OffsetEngineLayer pushOffset(
+    double dx,
+    double dy, {
+    ui.EngineLayer oldLayer,
+  }) {
     final Matrix4 matrix = Matrix4.translationValues(dx, dy, 0.0);
     final TransformLayer layer = TransformLayer(matrix);
     pushLayer(layer);
@@ -134,8 +156,11 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   }
 
   @override
-  ui.OpacityEngineLayer pushOpacity(int alpha,
-      {ui.EngineLayer oldLayer, ui.Offset offset = ui.Offset.zero}) {
+  ui.OpacityEngineLayer pushOpacity(
+    int alpha, {
+    ui.EngineLayer oldLayer,
+    ui.Offset offset = ui.Offset.zero,
+  }) {
     final OpacityLayer layer = OpacityLayer(alpha, offset);
     pushLayer(layer);
     return layer;
@@ -158,14 +183,19 @@ class LayerSceneBuilder implements ui.SceneBuilder {
 
   @override
   ui.ShaderMaskEngineLayer pushShaderMask(
-      ui.Shader shader, ui.Rect maskRect, ui.BlendMode blendMode,
-      {ui.EngineLayer oldLayer}) {
+    ui.Shader shader,
+    ui.Rect maskRect,
+    ui.BlendMode blendMode, {
+    ui.EngineLayer oldLayer,
+  }) {
     throw UnimplementedError();
   }
 
   @override
-  ui.TransformEngineLayer pushTransform(Float64List matrix4,
-      {ui.EngineLayer oldLayer}) {
+  ui.TransformEngineLayer pushTransform(
+    Float64List matrix4, {
+    ui.EngineLayer oldLayer,
+  }) {
     final Matrix4 matrix = Matrix4.fromList(matrix4);
     pushLayer(TransformLayer(matrix));
     return null;
@@ -201,8 +231,15 @@ class LayerSceneBuilder implements ui.SceneBuilder {
   }
 
   @override
-  void setProperties(double width, double height, double insetTop,
-      double insetRight, double insetBottom, double insetLeft, bool focusable) {
+  void setProperties(
+    double width,
+    double height,
+    double insetTop,
+    double insetRight,
+    double insetBottom,
+    double insetLeft,
+    bool focusable,
+  ) {
     throw UnimplementedError();
   }
 }
diff --git a/lib/web_ui/lib/src/engine/surface/scene_builder.dart b/lib/web_ui/lib/src/engine/surface/scene_builder.dart
index 990b8f3fcb1a8..52e8d01420a3d 100644
--- a/lib/web_ui/lib/src/engine/surface/scene_builder.dart
+++ b/lib/web_ui/lib/src/engine/surface/scene_builder.dart
@@ -9,8 +9,7 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
     _surfaceStack.add(PersistedScene(_lastFrameScene));
   }
 
-  final List<PersistedContainerSurface> _surfaceStack =
-      <PersistedContainerSurface>[];
+  final List<PersistedContainerSurface> _surfaceStack = <PersistedContainerSurface>[];
 
   /// The scene built by this scene builder.
   ///
@@ -19,8 +18,7 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
     assert(() {
       if (_surfaceStack.length != 1) {
         final String surfacePrintout = _surfaceStack
-            .map<Type>((PersistedContainerSurface surface) =>
-                surface.runtimeType)
+            .map<Type>((PersistedContainerSurface surface) => surface.runtimeType)
             .toList()
             .join(', ');
         throw Exception('Incorrect sequence of push/pop operations while '
@@ -65,7 +63,9 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.OffsetEngineLayer pushOffset(double dx, double dy, {
+  ui.OffsetEngineLayer pushOffset(
+    double dx,
+    double dy, {
     ui.OffsetEngineLayer oldLayer,
   }) {
     return _pushSurface(PersistedOffset(oldLayer, dx, dy));
@@ -77,7 +77,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.TransformEngineLayer pushTransform(Float64List matrix4, {
+  ui.TransformEngineLayer pushTransform(
+    Float64List matrix4, {
     ui.TransformEngineLayer oldLayer,
   }) {
     if (matrix4 == null) {
@@ -96,7 +97,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
   @override
-  ui.ClipRectEngineLayer pushClipRect(ui.Rect rect, {
+  ui.ClipRectEngineLayer pushClipRect(
+    ui.Rect rect, {
     ui.Clip clipBehavior = ui.Clip.antiAlias,
     ui.ClipRectEngineLayer oldLayer,
   }) {
@@ -111,7 +113,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ClipRRectEngineLayer pushClipRRect(ui.RRect rrect, {
+  ui.ClipRRectEngineLayer pushClipRRect(
+    ui.RRect rrect, {
     ui.Clip clipBehavior,
     ui.ClipRRectEngineLayer oldLayer,
   }) {
@@ -124,7 +127,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ClipPathEngineLayer pushClipPath(ui.Path path, {
+  ui.ClipPathEngineLayer pushClipPath(
+    ui.Path path, {
     ui.Clip clipBehavior = ui.Clip.antiAlias,
     ui.ClipPathEngineLayer oldLayer,
   }) {
@@ -142,7 +146,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.OpacityEngineLayer pushOpacity(int alpha, {
+  ui.OpacityEngineLayer pushOpacity(
+    int alpha, {
     ui.Offset offset = ui.Offset.zero,
     ui.OpacityEngineLayer oldLayer,
   }) {
@@ -160,7 +165,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.ColorFilterEngineLayer pushColorFilter(ui.ColorFilter filter, {
+  ui.ColorFilterEngineLayer pushColorFilter(
+    ui.ColorFilter filter, {
     ui.ColorFilterEngineLayer oldLayer,
   }) {
     assert(filter != null);
@@ -174,7 +180,8 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   ///
   /// See [pop] for details about the operation stack.
   @override
-  ui.BackdropFilterEngineLayer pushBackdropFilter(ui.ImageFilter filter, {
+  ui.BackdropFilterEngineLayer pushBackdropFilter(
+    ui.ImageFilter filter, {
     ui.BackdropFilterEngineLayer oldLayer,
   }) {
     return _pushSurface(PersistedBackdropFilter(oldLayer, filter));
@@ -280,8 +287,7 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// for more details.
   @override
   void addPerformanceOverlay(int enabledOptions, ui.Rect bounds) {
-    _addPerformanceOverlay(
-        enabledOptions, bounds.left, bounds.right, bounds.top, bounds.bottom);
+    _addPerformanceOverlay(enabledOptions, bounds.left, bounds.right, bounds.top, bounds.bottom);
   }
 
   /// Whether we've already warned the user about the lack of the performance
@@ -290,12 +296,16 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// We use this to avoid spamming the console with redundant warning messages.
   static bool _webOnlyDidWarnAboutPerformanceOverlay = false;
 
-  void _addPerformanceOverlay(int enabledOptions, double left, double right,
-      double top, double bottom) {
+  void _addPerformanceOverlay(
+    int enabledOptions,
+    double left,
+    double right,
+    double top,
+    double bottom,
+  ) {
     if (!_webOnlyDidWarnAboutPerformanceOverlay) {
       _webOnlyDidWarnAboutPerformanceOverlay = true;
-      html.window.console
-          .warn('The performance overlay isn\'t supported on the web');
+      html.window.console.warn('The performance overlay isn\'t supported on the web');
     }
   }
 
@@ -316,8 +326,7 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
     if (willChangeHint) {
       hints |= 2;
     }
-    _addSurface(
-        persistedPictureFactory(offset.dx, offset.dy, picture, hints));
+    _addSurface(persistedPictureFactory(offset.dx, offset.dy, picture, hints));
   }
 
   /// Adds a backend texture to the scene.
@@ -325,17 +334,18 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// The texture is scaled to the given size and rasterized at the given
   /// offset.
   @override
-  void addTexture(int textureId,
-      {ui.Offset offset = ui.Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      bool freeze = false}) {
+  void addTexture(
+    int textureId, {
+    ui.Offset offset = ui.Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    bool freeze = false,
+  }) {
     assert(offset != null, 'Offset argument was null');
     _addTexture(offset.dx, offset.dy, width, height, textureId);
   }
 
-  void _addTexture(
-      double dx, double dy, double width, double height, int textureId) {
+  void _addTexture(double dx, double dy, double width, double height, int textureId) {
     // In test mode, allow this to be a no-op.
     if (!ui.debugEmulateFlutterTesterEnvironment) {
       throw UnimplementedError('Textures are not supported in Flutter Web');
@@ -382,17 +392,24 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// (Fuchsia-only) Adds a scene rendered by another application to the scene
   /// for this application.
   @override
-  void addChildScene(
-      {ui.Offset offset = ui.Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      ui.SceneHost sceneHost,
-      bool hitTestable = true}) {
+  void addChildScene({
+    ui.Offset offset = ui.Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    ui.SceneHost sceneHost,
+    bool hitTestable = true,
+  }) {
     _addChildScene(offset.dx, offset.dy, width, height, sceneHost, hitTestable);
   }
 
-  void _addChildScene(double dx, double dy, double width, double height,
-      ui.SceneHost sceneHost, bool hitTestable) {
+  void _addChildScene(
+    double dx,
+    double dy,
+    double width,
+    double height,
+    ui.SceneHost sceneHost,
+    bool hitTestable,
+  ) {
     throw UnimplementedError();
   }
 
@@ -489,8 +506,15 @@ class SurfaceSceneBuilder implements ui.SceneBuilder {
   /// Set properties on the linked scene.  These properties include its bounds,
   /// as well as whether it can be the target of focus events or not.
   @override
-  void setProperties(double width, double height, double insetTop,
-      double insetRight, double insetBottom, double insetLeft, bool focusable) {
+  void setProperties(
+    double width,
+    double height,
+    double insetTop,
+    double insetRight,
+    double insetBottom,
+    double insetLeft,
+    bool focusable,
+  ) {
     throw UnimplementedError();
   }
 }
diff --git a/lib/web_ui/lib/src/ui/compositing.dart b/lib/web_ui/lib/src/ui/compositing.dart
index af4f39a90e856..d77249eb51775 100644
--- a/lib/web_ui/lib/src/ui/compositing.dart
+++ b/lib/web_ui/lib/src/ui/compositing.dart
@@ -117,7 +117,9 @@ abstract class SceneBuilder {
   /// This is equivalent to [pushTransform] with a matrix with only translation.
   ///
   /// See [pop] for details about the operation stack.
-  OffsetEngineLayer pushOffset(double dx, double dy, {
+  OffsetEngineLayer pushOffset(
+    double dx,
+    double dy, {
     OffsetEngineLayer oldLayer,
   });
 
@@ -126,7 +128,8 @@ abstract class SceneBuilder {
   /// The objects are transformed by the given matrix before rasterization.
   ///
   /// See [pop] for details about the operation stack.
-  TransformEngineLayer pushTransform(Float64List matrix4, {
+  TransformEngineLayer pushTransform(
+    Float64List matrix4, {
     TransformEngineLayer oldLayer,
   });
 
@@ -136,7 +139,8 @@ abstract class SceneBuilder {
   ///
   /// See [pop] for details about the operation stack, and [Clip] for different clip modes.
   /// By default, the clip will be anti-aliased (clip = [Clip.antiAlias]).
-  ClipRectEngineLayer pushClipRect(Rect rect, {
+  ClipRectEngineLayer pushClipRect(
+    Rect rect, {
     Clip clipBehavior = Clip.antiAlias,
     ClipRectEngineLayer oldLayer,
   });
@@ -146,7 +150,8 @@ abstract class SceneBuilder {
   /// Rasterization outside the given rounded rectangle is discarded.
   ///
   /// See [pop] for details about the operation stack.
-  ClipRRectEngineLayer pushClipRRect(RRect rrect, {
+  ClipRRectEngineLayer pushClipRRect(
+    RRect rrect, {
     Clip clipBehavior,
     ClipRRectEngineLayer oldLayer,
   });
@@ -156,7 +161,8 @@ abstract class SceneBuilder {
   /// Rasterization outside the given path is discarded.
   ///
   /// See [pop] for details about the operation stack.
-  ClipPathEngineLayer pushClipPath(Path path, {
+  ClipPathEngineLayer pushClipPath(
+    Path path, {
     Clip clipBehavior = Clip.antiAlias,
     ClipPathEngineLayer oldLayer,
   });
@@ -169,7 +175,8 @@ abstract class SceneBuilder {
   /// opacity).
   ///
   /// See [pop] for details about the operation stack.
-  OpacityEngineLayer pushOpacity(int alpha, {
+  OpacityEngineLayer pushOpacity(
+    int alpha, {
     Offset offset = Offset.zero,
     OpacityEngineLayer oldLayer,
   });
@@ -184,7 +191,8 @@ abstract class SceneBuilder {
   /// {@macro dart.ui.sceneBuilder.oldLayerVsRetained}
   ///
   /// See [pop] for details about the operation stack.
-  ColorFilterEngineLayer pushColorFilter(ColorFilter filter, {
+  ColorFilterEngineLayer pushColorFilter(
+    ColorFilter filter, {
     ColorFilterEngineLayer oldLayer,
   });
 
@@ -194,7 +202,8 @@ abstract class SceneBuilder {
   /// rasterizing the given objects.
   ///
   /// See [pop] for details about the operation stack.
-  BackdropFilterEngineLayer pushBackdropFilter(ImageFilter filter, {
+  BackdropFilterEngineLayer pushBackdropFilter(
+    ImageFilter filter, {
     BackdropFilterEngineLayer oldLayer,
   });
 
@@ -204,7 +213,10 @@ abstract class SceneBuilder {
   /// rectangle using the given blend mode.
   ///
   /// See [pop] for details about the operation stack.
-  ShaderMaskEngineLayer pushShaderMask(Shader shader, Rect maskRect, BlendMode blendMode, {
+  ShaderMaskEngineLayer pushShaderMask(
+    Shader shader,
+    Rect maskRect,
+    BlendMode blendMode, {
     ShaderMaskEngineLayer oldLayer,
   });
 
@@ -286,11 +298,13 @@ abstract class SceneBuilder {
   ///
   /// The texture is scaled to the given size and rasterized at the given
   /// offset.
-  void addTexture(int textureId,
-      {Offset offset = Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      bool freeze = false});
+  void addTexture(
+    int textureId, {
+    Offset offset = Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    bool freeze = false,
+  });
 
   /// Adds a platform view (e.g an iOS UIView) to the scene.
   ///
@@ -317,12 +331,13 @@ abstract class SceneBuilder {
 
   /// (Fuchsia-only) Adds a scene rendered by another application to the scene
   /// for this application.
-  void addChildScene(
-      {Offset offset = Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      SceneHost sceneHost,
-      bool hitTestable = true});
+  void addChildScene({
+    Offset offset = Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    SceneHost sceneHost,
+    bool hitTestable = true,
+  });
 
   /// Sets a threshold after which additional debugging information should be
   /// recorded.
@@ -369,8 +384,15 @@ abstract class SceneBuilder {
 
   /// Set properties on the linked scene.  These properties include its bounds,
   /// as well as whether it can be the target of focus events or not.
-  void setProperties(double width, double height, double insetTop,
-      double insetRight, double insetBottom, double insetLeft, bool focusable);
+  void setProperties(
+    double width,
+    double height,
+    double insetTop,
+    double insetRight,
+    double insetBottom,
+    double insetLeft,
+    bool focusable,
+  );
 }
 
 /// A handle for the framework to hold and retain an engine layer across frames.
@@ -390,10 +412,11 @@ class SceneHost {
   ///
   /// The SceneHost takes ownership of the provided ViewHolder token.
   SceneHost(
-      dynamic viewHolderToken,
-      void Function() viewConnectedCallback,
-      void Function() viewDisconnectedCallback,
-      void Function(bool) viewStateChangedCallback);
+    dynamic viewHolderToken,
+    void Function() viewConnectedCallback,
+    void Function() viewDisconnectedCallback,
+    void Function(bool) viewStateChangedCallback,
+  );
 
   /// Releases the resources associated with the SceneHost.
   ///
@@ -402,8 +425,15 @@ class SceneHost {
 
   /// Set properties on the linked scene.  These properties include its bounds,
   /// as well as whether it can be the target of focus events or not.
-  void setProperties(double width, double height, double insetTop,
-      double insetRight, double insetBottom, double insetLeft, bool focusable) {
+  void setProperties(
+    double width,
+    double height,
+    double insetTop,
+    double insetRight,
+    double insetBottom,
+    double insetLeft,
+    bool focusable,
+  ) {
     throw UnimplementedError();
   }
 }

From b22300905b31ab8e4b73d5833fd10a5e72f998e1 Mon Sep 17 00:00:00 2001
From: Jim Graham <flar@google.com>
Date: Thu, 19 Dec 2019 10:51:52 -0800
Subject: [PATCH 3/4] One more method signature fix.

---
 lib/ui/compositing.dart | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/lib/ui/compositing.dart b/lib/ui/compositing.dart
index 4025754ef266d..e5191e457025c 100644
--- a/lib/ui/compositing.dart
+++ b/lib/ui/compositing.dart
@@ -680,12 +680,13 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
 
   /// (Fuchsia-only) Adds a scene rendered by another application to the scene
   /// for this application.
-  void addChildScene(
-      {Offset offset = Offset.zero,
-      double width = 0.0,
-      double height = 0.0,
-      SceneHost sceneHost,
-      bool hitTestable = true}) {
+  void addChildScene({
+    Offset offset = Offset.zero,
+    double width = 0.0,
+    double height = 0.0,
+    SceneHost sceneHost,
+    bool hitTestable = true,
+  }) {
     _addChildScene(offset.dx, offset.dy, width, height, sceneHost, hitTestable);
   }
 

From d1cb1543c39ad841a4397e7c85ea3336caaf3c19 Mon Sep 17 00:00:00 2001
From: Jim Graham <flar@google.com>
Date: Thu, 19 Dec 2019 11:15:42 -0800
Subject: [PATCH 4/4] Fix analyzer issues.

---
 lib/ui/compositing.dart | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/ui/compositing.dart b/lib/ui/compositing.dart
index e5191e457025c..f2b36ca95212c 100644
--- a/lib/ui/compositing.dart
+++ b/lib/ui/compositing.dart
@@ -22,7 +22,9 @@ class Scene extends NativeFieldWrapperClass2 {
   /// Creates a raster image representation of the current state of the scene.
   /// This is a slow operation that is performed on a background thread.
   Future<Image> toImage(int width, int height) {
-    if (width <= 0 || height <= 0) throw Exception('Invalid image dimensions.');
+    if (width <= 0 || height <= 0) {
+      throw Exception('Invalid image dimensions.');
+    }
     return _futurize((_Callback<Image> callback) => _toImage(width, height, callback));
   }
 
@@ -615,9 +617,7 @@ class SceneBuilder extends NativeFieldWrapperClass2 {
     bool isComplexHint = false,
     bool willChangeHint = false,
   }) {
-    int hints = 0;
-    if (isComplexHint) hints |= 1;
-    if (willChangeHint) hints |= 2;
+    final int hints = (isComplexHint ? 1 : 0) | (willChangeHint ? 2 : 0);
     _addPicture(offset.dx, offset.dy, picture, hints);
   }