Cleanup: Remove unneeded forward declarations in base, dbug, gpu, ipc, jingle, and media.

base/message_loop.h

Index: base/message_loop.h
===================================================================
--- base/message_loop.h	(revision 109364)
+++ base/message_loop.h	(working copy)
@@ -45,10 +45,6 @@
 class Histogram;
 }
 
-namespace tracked_objects {
-class Births;
-}
-
 // A MessageLoop is used to process events for a particular thread.  There is
 // at most one MessageLoop instance per thread.
 //
@@ -692,8 +688,8 @@
   bool WatchFileDescriptor(int fd,
                            bool persistent,
                            Mode mode,
-                           FileDescriptorWatcher *controller,
-                           Watcher *delegate);
+                           FileDescriptorWatcher* controller,
+                           Watcher* delegate);
 
  private:
   base::MessagePumpLibevent* pump_io() {