DrMemory suppression due to r6811.

BUG=3655
TBR=pthatcher@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/16209004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6820 4adac7df-926f-26a2-2b94-8c16560cd09d