Adding some features to proxy.h, and restructuring the macros.

webrtc/api/rtpreceiverinterface.h

Index: webrtc/api/rtpreceiverinterface.h
diff --git a/webrtc/api/rtpreceiverinterface.h b/webrtc/api/rtpreceiverinterface.h
index 53a37398cfc9222c6c6528640920fb619d728a1f..103df473e3197d45ff04ed11eb4e1d90e5299e9d 100644
--- a/webrtc/api/rtpreceiverinterface.h
+++ b/webrtc/api/rtpreceiverinterface.h
@@ -66,13 +66,14 @@ class RtpReceiverInterface : public rtc::RefCountInterface {
 
 // Define proxy for RtpReceiverInterface.
 BEGIN_SIGNALING_PROXY_MAP(RtpReceiver)
-PROXY_CONSTMETHOD0(rtc::scoped_refptr<MediaStreamTrackInterface>, track)
-PROXY_CONSTMETHOD0(cricket::MediaType, media_type)
-PROXY_CONSTMETHOD0(std::string, id)
-PROXY_CONSTMETHOD0(RtpParameters, GetParameters);
-PROXY_METHOD1(bool, SetParameters, const RtpParameters&)
-PROXY_METHOD1(void, SetObserver, RtpReceiverObserverInterface*);
-END_SIGNALING_PROXY()
+  PROXY_SIGNALING_THREAD_DESTRUCTOR()
+  PROXY_CONSTMETHOD0(rtc::scoped_refptr<MediaStreamTrackInterface>, track)
+  PROXY_CONSTMETHOD0(cricket::MediaType, media_type)
+  PROXY_CONSTMETHOD0(std::string, id)
+  PROXY_CONSTMETHOD0(RtpParameters, GetParameters);
+  PROXY_METHOD1(bool, SetParameters, const RtpParameters&)
+  PROXY_METHOD1(void, SetObserver, RtpReceiverObserverInterface*);
+END_PROXY_MAP()
 
 }  // namespace webrtc