Remove WEBRTC_TRACE completely when tracing is disabled.

This will help to cut the code size since those logging messages are removed.
Contributed by Henrik Ellner.
Review URL: https://webrtc-codereview.appspot.com/1125004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@3560 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed