BUG=387
TESTED=libyuvTest.ARGBRect_Opt and libyuvTest.SetPlane_Opt
R=harryjin@google.com

Review URL: https://webrtc-codereview.appspot.com/35589004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1217 16f28f9a-4ce2-e073-06de-1de4eb20be90