a0591b5473
To make the HasOneRef/IsMutable hack work, also had to change the video_frame_buffer method to return a const ref to a scoped_ref_ptr, to not imply an AddRef. BUG=webrtc:5682 Review-Url: https://codereview.webrtc.org/1900673002 Cr-Commit-Position: refs/heads/master@{#12557}