Struct was added prematurely and triggers a warning with -Wextern-c-compat in latest clang. R=henrika@webrtc.org BUG= Review URL: https://webrtc-codereview.appspot.com/7119004 git-svn-id: http://webrtc.googlecode.com/svn/trunk@5383 4adac7df-926f-26a2-2b94-8c16560cd09d