void PageHandler::OnSynchronousSwapCompositorFrame(
    viz::CompositorFrameMetadata frame_metadata) {
  if (has_compositor_frame_metadata_) {
    last_compositor_frame_metadata_ =
        std::move(next_compositor_frame_metadata_);
  } else {
    last_compositor_frame_metadata_ = frame_metadata.Clone();
  }
  next_compositor_frame_metadata_ = std::move(frame_metadata);

  has_compositor_frame_metadata_ = true;

  if (screencast_enabled_)
    InnerSwapCompositorFrame();
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.