base: Remove unused code in the message-loop.

base/message_loop/message_loop.h

Index: base/message_loop/message_loop.h
diff --git a/base/message_loop/message_loop.h b/base/message_loop/message_loop.h
index 3520b72516f4dfc80c8286f7b8bb64d4606c7cfa..0eb180352d324eb1f9a3dbff6dbe58eaa44e1bf2 100644
--- a/base/message_loop/message_loop.h
+++ b/base/message_loop/message_loop.h
@@ -586,10 +586,6 @@ class BASE_EXPORT MessageLoopForUI : public MessageLoop {
     return static_cast<MessageLoopForUI*>(loop);
   }
 
-#if defined(OS_WIN)
-  void DidProcessMessage(const MSG& message);
-#endif  // defined(OS_WIN)
-
 #if defined(OS_IOS)
   // On iOS, the main message loop cannot be Run().  Instead call Attach(),
   // which connects this MessageLoop to the UI thread's CFRunLoop and allows