Works around a multiple definition error from webrtc and libjingle. Corresponds to the libjingle change here: https://critique.corp.google.com/#review/55489575-p10 TESTED=trybots R=wu@webrtc.org Review URL: https://webrtc-codereview.appspot.com/2809004 git-svn-id: http://webrtc.googlecode.com/svn/trunk@5025 4adac7df-926f-26a2-2b94-8c16560cd09d