cricket::VideoFrameFactory: Don't overwrite frames in use

VideoFrameFactory has a single frame buffer that is used when scaling frames. If the previous frame is still in use, we need to allocate a new frame.

BUG=4347
R=perkj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/36359004

Cr-Commit-Position: refs/heads/master@{#8549}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8549 4adac7df-926f-26a2-2b94-8c16560cd09d
4 files changed