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

chrome/browser/media/webrtc_logging_handler_host.cc

Index: chrome/browser/media/webrtc_logging_handler_host.cc
diff --git a/chrome/browser/media/webrtc_logging_handler_host.cc b/chrome/browser/media/webrtc_logging_handler_host.cc
index 611bc520ae000b0391379c2253f77e16db739441..31759bb679a642fd803384754989f1021ff65d25 100644
--- a/chrome/browser/media/webrtc_logging_handler_host.cc
+++ b/chrome/browser/media/webrtc_logging_handler_host.cc
@@ -203,6 +203,14 @@ void WebRtcLoggingHandlerHost::DiscardLog(const GenericDoneCallback& callback) {
   FireGenericDoneCallback(&discard_callback, true, "");
 }
 
+void WebRtcLoggingHandlerHost::LogMessage(const std::string& message) {
+  BrowserThread::PostTask(
+      BrowserThread::IO,
+      FROM_HERE,
+      base::Bind(
+          &WebRtcLoggingHandlerHost::AddLogMessageFromBrowser, this, message));
+}
+
 void WebRtcLoggingHandlerHost::OnChannelClosing() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   if (logging_state_ == STARTED || logging_state_ == STOPPED) {
@@ -234,6 +242,13 @@ bool WebRtcLoggingHandlerHost::OnMessageReceived(const IPC::Message& message,
   return handled;
 }
 
+void WebRtcLoggingHandlerHost::AddLogMessageFromBrowser(
+    const std::string& message) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  if (logging_state_ == STARTED)
+    LogToCircularBuffer(message);
+}
+
 void WebRtcLoggingHandlerHost::OnAddLogMessage(const std::string& message) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   if (logging_state_ == STARTED || logging_state_ == STOPPING)