Propagate VideoFrameFeedback to wrapped media::VideoFrame

This will allow WebrtcVideoFrameAdapter to set feedback.
Currently, it may get a wrapped frame in some cases.
WebrtcVideoFrameAdapter is a logical place to attach feedback, since it's
the wrapper of VideoFrame available inside WebRTC.

Bug: chromium:1134073
Change-Id: Id955609dc00d4555294cd39192b55db66ac8f72a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2440513
Auto-Submit: Ilya Nikolaevskiy <ilnik@chromium.org>
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812700}

media/base/video_frame.cc

@@ -1299,6 +1299,12 @@ VideoFrame::~VideoFrame() {
     std::move(mailbox_holders_release_cb_).Run(release_sync_token);
   }
 
+  // Someone might be monitoring original wrapped frame for feedback.
+  // Ensure all accumulated feedback is propagated to the original frame.
+  if (wrapped_frame_) {
+    wrapped_frame_->feedback()->Combine(feedback_);
+  }
+
   for (auto& callback : done_callbacks_)
     std::move(callback).Run();
 }