[Extended FAB][AppBar] Fix Extended FAB behavior demo to shrink and extend as expected.

Also:
- Library fix to the AppBarLayout calculations for extended FAB versus FAB visibility.
- Removed the M3 Expressive toolbar min heights in favor of actionBarSize.

Resolves #4751

PiperOrigin-RevId: 764380548

Author: kendrickumstattd

catalog/java/io/material/catalog/application/theme/res/values/styles.xml

@@ -19,7 +19,7 @@
   <!-- For the catalog we know that toolbars will always be on top of a "surface" color,
        so it's better for them to have no background, especially because it's common for
        toolbars to be nested in an AppBarLayout which has its own background handling. -->
-  <style name="Widget.Catalog.Toolbar" parent="Widget.Material3.Toolbar.OnSurface" />
+  <style name="Widget.Catalog.Toolbar" parent="Widget.Material3Expressive.Toolbar.OnSurface" />
 
   <style name="Widget.Catalog.Toolbar.WithCloseButton">
     <item name="navigationContentDescription">@string/toolbar_navigation_close_description</item>

lib/java/com/google/android/material/appbar/AppBarLayout.java

@@ -1012,17 +1012,22 @@ void onOffsetChanged(int offset) {
   public final int getMinimumHeightForVisibleOverlappingContent() {
     final int topInset = getTopInset();
     final int minHeight = getMinimumHeight();
+
+    // If this layout has a min height, use it (doubled) or, if this doesn't clear the threshold,
+    // the min height.
     if (minHeight != 0) {
-      // If this layout has a min height, use it (doubled)
-      return (minHeight * 2) + topInset;
+      int idealHeight = (minHeight * 2) + topInset;
+      return idealHeight < getHeight() ? idealHeight : minHeight + topInset;
     }
 
-    // Otherwise, we'll use twice the min height of our last child
+    // Otherwise, we'll ideally use twice the min height of our last child or, if this doesn't
+    // clear the threshold, the min height of our last child.
     final int childCount = getChildCount();
     final int lastChildMinHeight =
         childCount >= 1 ? getChildAt(childCount - 1).getMinimumHeight() : 0;
     if (lastChildMinHeight != 0) {
-      return (lastChildMinHeight * 2) + topInset;
+      int idealHeight = (lastChildMinHeight * 2) + topInset;
+      return idealHeight < getHeight() ? idealHeight : lastChildMinHeight + topInset;
     }
 
     // If we reach here then we don't have a min height explicitly set. Instead we'll take a

lib/java/com/google/android/material/appbar/res/values/styles.xml

@@ -52,21 +52,18 @@
   <style name="Widget.Material3Expressive.Toolbar" parent="Widget.Material3.Toolbar">
     <item name="titleTextAppearance">@macro/m3_comp_app_bar_small_title_font</item>
     <item name="subtitleTextAppearance">@macro/m3_comp_app_bar_small_subtitle_font</item>
-    <item name="android:minHeight">@dimen/m3_comp_app_bar_small_container_height</item>
     <item name="android:layout_marginEnd">4dp</item>
   </style>
 
   <style name="Widget.Material3Expressive.Toolbar.OnSurface" parent="Widget.Material3.Toolbar.OnSurface">
     <item name="titleTextAppearance">@macro/m3_comp_app_bar_small_title_font</item>
     <item name="subtitleTextAppearance">@macro/m3_comp_app_bar_small_subtitle_font</item>
-    <item name="android:minHeight">@dimen/m3_comp_app_bar_small_container_height</item>
     <item name="android:layout_marginEnd">4dp</item>
   </style>
 
   <style name="Widget.Material3Expressive.Toolbar.Surface" parent="Widget.Material3.Toolbar.Surface">
     <item name="titleTextAppearance">@macro/m3_comp_app_bar_small_title_font</item>
     <item name="subtitleTextAppearance">@macro/m3_comp_app_bar_small_subtitle_font</item>
-    <item name="android:minHeight">@dimen/m3_comp_app_bar_small_container_height</item>
     <item name="android:layout_marginEnd">4dp</item>
   </style>