Additional disabled tests in rtc_unittests.

It appears https://review.webrtc.org/30449004 was
not enough to get rtc_unittests up and running.

BUG=3836
TEST=Locally passing rtc_unittests on Mac Debug.
R=henrike@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/27559004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7241 4adac7df-926f-26a2-2b94-8c16560cd09d