BUG=253
TEST=libyuv_unittest,ncval,trybots
R=fbarchard@google.com

Review URL: https://webrtc-codereview.appspot.com/2054006

git-svn-id: http://libyuv.googlecode.com/svn/trunk@766 16f28f9a-4ce2-e073-06de-1de4eb20be90