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

webrtc/api/dtmfsender.h

Index: webrtc/api/dtmfsender.h
diff --git a/webrtc/api/dtmfsender.h b/webrtc/api/dtmfsender.h
index c85557f2e150177f82bb209643b861402c299013..d4e8f06d9e1e78ebe6bd33726ed7d59121bfca29 100644
--- a/webrtc/api/dtmfsender.h
+++ b/webrtc/api/dtmfsender.h
@@ -105,6 +105,7 @@ class DtmfSender
 
 // Define proxy for DtmfSenderInterface.
 BEGIN_SIGNALING_PROXY_MAP(DtmfSender)
+  PROXY_SIGNALING_THREAD_DESTRUCTOR()
   PROXY_METHOD1(void, RegisterObserver, DtmfSenderObserverInterface*)
   PROXY_METHOD0(void, UnregisterObserver)
   PROXY_METHOD0(bool, CanInsertDtmf)
@@ -113,7 +114,7 @@ BEGIN_SIGNALING_PROXY_MAP(DtmfSender)
   PROXY_CONSTMETHOD0(std::string, tones)
   PROXY_CONSTMETHOD0(int, duration)
   PROXY_CONSTMETHOD0(int, inter_tone_gap)
-END_SIGNALING_PROXY()
+END_PROXY_MAP()
 
 // Get DTMF code from the DTMF event character.
 bool GetDtmfCode(char tone, int* code);