Add a trace for WebRTC initialization time

third_party/libjingle/overrides/init_webrtc.cc

Index: third_party/libjingle/overrides/init_webrtc.cc
diff --git a/third_party/libjingle/overrides/init_webrtc.cc b/third_party/libjingle/overrides/init_webrtc.cc
index cc0ad5f26ffb839a1a2f6ec90825a8bc9418e2d5..746f8831cd10fca3713c4caf013c1d4a38678e4e 100644
--- a/third_party/libjingle/overrides/init_webrtc.cc
+++ b/third_party/libjingle/overrides/init_webrtc.cc
@@ -71,6 +71,8 @@ static base::FilePath GetLibPeerConnectionPath() {
 }
 
 bool InitializeWebRtcModule() {
+  TRACE_EVENT0("webrtc", "InitializeWebRtcModule");
+
   if (g_create_webrtc_media_engine)
     return true;  // InitializeWebRtcModule has already been called.