Re-enable the messagequeue unittests. These were commented out at one point but never reenabled.
Re-enable the messagequeue unittests. These were commented out at one point but never reenabled.

R=hellner@chromium.org, henrike@webrtc.org
CC=juberti@webrtc.org,pthatcher@webrtc.org
BUG=

Review URL: https://webrtc-codereview.appspot.com/41499004

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: d7de1209ae60c2e38e38aced8864589b1f2891c5

sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc