Add RTC_ prefix to contructormagic macros.

webrtc/base/multipart.h

Index: webrtc/base/multipart.h
diff --git a/webrtc/base/multipart.h b/webrtc/base/multipart.h
index 1eeef5ce2dc6408f88ab09401e490b54b9ea33aa..a099230cc50c1e6687dcb1f5308a1f054f470b19 100644
--- a/webrtc/base/multipart.h
+++ b/webrtc/base/multipart.h
@@ -75,7 +75,7 @@ class MultipartStream : public StreamInterface, public sigslot::has_slots<> {
   size_t current_;  // The index into parts_ of the current read position.
   size_t position_;  // The current read position in bytes.
 
-  DISALLOW_COPY_AND_ASSIGN(MultipartStream);
+  RTC_DISALLOW_COPY_AND_ASSIGN(MultipartStream);
 };
 
 }  // namespace rtc