Reland CL to implement browser-side logging to WebRtc log.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 14c0cd21b9bd75b37db4edee75a3f5a79ea044f4..60881ea5859cab909e611ff026c3e9236e29274b 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -1516,6 +1516,11 @@ void RenderProcessHostImpl::DisableAecDump() {
       base::Bind(&RenderProcessHostImpl::SendDisableAecDumpToRenderer,
                  weak_factory_.GetWeakPtr()));
 }
+
+void RenderProcessHostImpl::SetWebRtcLogMessageCallback(
+    base::Callback<void(const std::string&)> callback) {
+  webrtc_log_message_callback_ = callback;
+}
 #endif
 
 IPC::ChannelProxy* RenderProcessHostImpl::GetChannel() {
@@ -1882,6 +1887,14 @@ void RenderProcessHostImpl::EndFrameSubscription(int route_id) {
       route_id));
 }
 
+#if defined(ENABLE_WEBRTC)
+void RenderProcessHostImpl::WebRtcLogMessage(const std::string& message) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!webrtc_log_message_callback_.is_null())
+    webrtc_log_message_callback_.Run(message);
+}
+#endif
+
 void RenderProcessHostImpl::OnShutdownRequest() {
   // Don't shut down if there are active RenderViews, or if there are pending
   // RenderViews being swapped back in.