Disabling MixingTests due to race conditions.

BUG=1580
TBR=tommi

Review URL: https://webrtc-codereview.appspot.com/1285005

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@3762 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed