In r4966 this was disabled on Linux for WebRTC code in order to detect any new unused const variables.
This CL does the same for Mac.
BUG=none
TEST=added an unused const and verified compilation fails
when this patch is applied. Mac trybots passing as well.
R=andrew@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/2459004
git-svn-id: http://webrtc.googlecode.com/svn/trunk@4997 4adac7df-926f-26a2-2b94-8c16560cd09d