message: Add a sanity check of RTCVideoFrame in RTCMTLVideoView
  Cr-Commit-Position: refs/heads/main@{#35636}
diff: NSAssert(view == self.metalView, @"Receiving draw callbacks from foreign instance.");
  RTC_OBJC_TYPE(RTCVideoFrame) *videoFrame = self.videoFrame;
  // Skip rendering if we've already rendered this frame.
  - if (!videoFrame || videoFrame.timeStampNs == self.lastFrameTimeNs) {
  + if (!videoFrame || videoFrame.width <= 0 || videoFrame.height <= 0 ||
  + videoFrame.timeStampNs == self.lastFrameTimeNs) {
  return;
  }
  