hybrid_android_views_integration_test depends on NOP rendering calls for correctness

[flar]

This test is blocking an engine PR that ignores rendering calls that don't render anything. The test expects a second FlutterImageView which only contains non-rendering operations. If we stop recording those operations then the second FlutterImageView will not be generated and this is treated as a bug by the test.

One way to demonstrate the failure without the changes to the engine is to remove the offending calls from the platform and try to run the test - it will fail in the absence of these non-rendering calls. (Note that the indicated diffs are not necessarily an optimal suggested patch for the Framework, but they just serve to eliminate the cases of non-rendering calls which are encountered during this one test and demonstrate its change in expectations.)

There are 3 possible solutions here:

• Modify the test so that one or more of the indicated call sites below actually render something - thereby causing the operations to not be elided in the engine and the secondary FlutterImageView to be needed as per the current test expectations. (Does the test want the second View to be present in order to test its conditions properly?)
• Modify the test to have new expectations and patch the Framework to eliminate these non-rendering calls even in the absence of the engine's PR to elide these calls at the native level
• Modify the test to have new expectations and do a manual roll of the engine that elides the rendering operations along with the patch to the test so that it will expect the new results.

Framework patch to eliminate non-rendering calls

diff --git a/packages/flutter/lib/src/painting/box_border.dart b/packages/flutter/lib/src/painting/box_border.dart
index dfc9a606a5..954aa84671 100644
--- a/packages/flutter/lib/src/painting/box_border.dart
+++ b/packages/flutter/lib/src/painting/box_border.dart
@@ -188,6 +188,9 @@ abstract class BoxBorder extends ShapeBorder {
     // is always painted. There is no borderRadius parameter for
     // ShapeDecoration or Border, only for BoxDecoration, which doesn't call
     // this method.
+    if (paint.shader == null && paint.blendMode == BlendMode.srcOver && paint.color.alpha == 0) {
+      return;
+    }
     canvas.drawRect(rect, paint);
   }
 
diff --git a/packages/flutter/lib/src/rendering/proxy_box.dart b/packages/flutter/lib/src/rendering/proxy_box.dart
index a089fbe145..003385bbc7 100644
--- a/packages/flutter/lib/src/rendering/proxy_box.dart
+++ b/packages/flutter/lib/src/rendering/proxy_box.dart
@@ -2134,14 +2134,6 @@ class RenderPhysicalShape extends _RenderPhysicalModelBase<Path> {
 
     final Canvas canvas = context.canvas;
     if (elevation != 0.0 && paintShadows) {
-      // The drawShadow call doesn't add the region of the shadow to the
-      // picture's bounds, so we draw a hardcoded amount of extra space to
-      // account for the maximum potential area of the shadow.
-      // TODO(jsimmons): remove this when Skia does it for us.
-      canvas.drawRect(
-        offsetBounds.inflate(20.0),
-        _transparentPaint,
-      );
       canvas.drawShadow(
         offsetPath,
         shadowColor,
@@ -2151,10 +2143,12 @@ class RenderPhysicalShape extends _RenderPhysicalModelBase<Path> {
     }
     final bool usesSaveLayer = clipBehavior == Clip.antiAliasWithSaveLayer;
     if (!usesSaveLayer) {
-      canvas.drawPath(
-        offsetPath,
-        Paint()..color = color
-      );
+      if (color.alpha != 0) {
+        canvas.drawPath(
+            offsetPath,
+            Paint()..color = color
+        );
+      }
     }
     layer = context.pushClipPath(
       needsCompositing,

[flar]

This issue is the root cause behind this revert of the engine's NOP culling mechanism: flutter/engine#43721

[github-actions]

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