Previously input buffers would be filled incorrectly for sparsely packed buffers where stride is not equal to the plane width. Bug: webrtc:8478 Change-Id: I080fa3c354a27982bb996be8c1e41b103384e4bc Reviewed-on: https://webrtc-review.googlesource.com/17321 Reviewed-by: Magnus Jedvert <magjed@webrtc.org> Commit-Queue: Sami Kalliomäki <sakal@webrtc.org> Cr-Commit-Position: refs/heads/master@{#20550}