Use WeakPtr for RTCPeerConnectionHandler and RTCPeerConnectionTracker.

content/renderer/media/rtc_peer_connection_handler.h

Index: content/renderer/media/rtc_peer_connection_handler.h
diff --git a/content/renderer/media/rtc_peer_connection_handler.h b/content/renderer/media/rtc_peer_connection_handler.h
index e421bd356d2037284218ebd79a81d673eb99c38c..14a6256e1d9268e0f392bacdfad6de8ec1f916f0 100644
--- a/content/renderer/media/rtc_peer_connection_handler.h
+++ b/content/renderer/media/rtc_peer_connection_handler.h
@@ -108,7 +108,7 @@ class CONTENT_EXPORT RTCPeerConnectionHandler
   bool InitializeForTest(
       const blink::WebRTCConfiguration& server_configuration,
       const blink::WebMediaConstraints& options,
-      PeerConnectionTracker* peer_connection_tracker);
+      const base::WeakPtr<PeerConnectionTracker>& peer_connection_tracker);
 
   // blink::WebRTCPeerConnectionHandler implementation
   virtual bool initialize(
@@ -177,8 +177,6 @@ class CONTENT_EXPORT RTCPeerConnectionHandler
   // Tells the |client_| to close RTCPeerConnection.
   void CloseClientPeerConnection();
 
-  PeerConnectionTracker* peer_connection_tracker();
-
  protected:
   webrtc::PeerConnectionInterface* native_peer_connection() {
     return native_peer_connection_.get();
@@ -222,7 +220,7 @@ class CONTENT_EXPORT RTCPeerConnectionHandler
 
   ScopedVector<WebRtcMediaStreamAdapter> local_streams_;
 
-  PeerConnectionTracker* peer_connection_tracker_;
+  base::WeakPtr<PeerConnectionTracker> peer_connection_tracker_;
 
   MediaStreamTrackMetrics track_metrics_;