anchor.diff:      codecCompleter.complete(mockCodec);
       await tester.idle();
   
  -    final FrameInfo frame1 = FakeFrameInfo(20, 10, const Duration(milliseconds: 200));
  -    final FrameInfo frame2 = FakeFrameInfo(200, 100, const Duration(milliseconds: 400));
  +    final FrameInfo frame1 = FakeFrameInfo(const Duration(milliseconds: 200), image20x10);
  +    final FrameInfo frame2 = FakeFrameInfo(const Duration(milliseconds: 400), image200x100);
   
       mockCodec.completeNextFrame(frame1);
       await tester.idle(); // let nextFrameFuture complete
  
positive.code:     codecCompleter.complete(mockCodec);
      await tester.idle();
  
      final FrameInfo frame1 = FakeFrameInfo(20, 10, const Duration(milliseconds: 200));
      final FrameInfo frame2 = FakeFrameInfo(200, 100, const Duration(milliseconds: 400));
  
      mockCodec.completeNextFrame(frame1);
      await tester.idle(); // let nextFrameFuture complete
  
negative.code:     codecCompleter.complete(mockCodec);
      await tester.idle();
  
      final FrameInfo frame = FakeFrameInfo(const Duration(milliseconds: 200), image20x10);
      mockCodec.completeNextFrame(frame);
      await tester.idle();
  
  