Validate Gold integration (#163629)

Checking to see if Gold is processing image updates as it should be. 
Related to https://github.com/flutter/flutter/pull/163573

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packages/flutter/test/widgets/basic_test.dart

@@ -802,7 +802,7 @@ void main() {
   testWidgets('Inconsequential golden test', (WidgetTester tester) async {
     // The test validates the Flutter Gold integration. Any changes to the
     // golden file can be approved at any time.
-    await tester.pumpWidget(RepaintBoundary(child: Container(color: const Color(0xAAA61145))));
+    await tester.pumpWidget(RepaintBoundary(child: Container(color: const Color(0xAFF61145))));
 
     await tester.pumpAndSettle();
     await expectLater(