[vector_graphics]Add Null Check for Image Retrieval in listener.dart's onDrawImage Function (flutter#9211)

This PR adds error handling for [flutter#168364](flutter#168364)

## Pre-Review Checklist

Author: wyqlxf

packages/vector_graphics/CHANGELOG.md

@@ -1,6 +1,7 @@
-## NEXT
+## 1.1.19
 
-* Updates minimum supported SDK version to Flutter 3.27/Dart 3.6.
+* Updates minimum supported SDK version to Flutter 3.24/Dart 3.5.
+* Enhance image handling by adding validity checks and clear error messages for improved robustness and maintainability.
 
 ## 1.1.18
 

packages/vector_graphics/lib/src/listener.dart

@@ -773,7 +773,12 @@ class FlutterVectorGraphicsListener extends VectorGraphicsCodecListener {
   @override
   void onDrawImage(int imageId, double x, double y, double width, double height,
       Float64List? transform) {
-    final Image image = _images[imageId]!;
+    final Image? image = _images[imageId];
+    assert(image != null,
+        'Invalid imageId: $imageId. Image not found in _images.');
+    if (image == null) {
+      return;
+    }
     if (transform != null) {
       _canvas.save();
       _canvas.transform(transform);

packages/vector_graphics/pubspec.yaml

@@ -2,7 +2,7 @@ name: vector_graphics
 description: A vector graphics rendering package for Flutter using a binary encoding.
 repository: https://github.com/flutter/packages/tree/main/packages/vector_graphics
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+vector_graphics%22
-version: 1.1.18
+version: 1.1.19
 
 environment:
   sdk: ^3.6.0

packages/vector_graphics/test/listener_test.dart

@@ -144,6 +144,18 @@ void main() {
     expect(drawParagraph1.memberName, #drawParagraph);
     expect((drawParagraph1.positionalArguments[1] as Offset).dx, 58);
   });
+
+  test('should assert when imageId is invalid', () async {
+    final TestPictureFactory factory = TestPictureFactory();
+    final FlutterVectorGraphicsListener listener =
+        FlutterVectorGraphicsListener(
+      pictureFactory: factory,
+    );
+    listener.onImage(0, 0, base64.decode(bluePngPixel));
+    await listener.waitForImageDecode();
+    expect(() => listener.onDrawImage(2, 10, 10, 100, 100, null),
+        throwsAssertionError);
+  });
 }
 
 class TestPictureFactory implements PictureFactory {