Use a direct include of the message_loop header in chrome/browser/, part 7.

chrome/browser/notifications/balloon_collection_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Handles the visible notification (or balloons).
 
 #ifndef CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_
 #define CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_
 
 #include <deque>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "chrome/browser/notifications/balloon_collection.h"
 #include "chrome/browser/notifications/balloon_collection_base.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/rect.h"
 
 // Mac balloons grow from the top down and have close buttons on top, so
 // offsetting is not necessary for easy multiple-closing.  Other platforms grow
 // from the bottom up and have close buttons on top, so it is necessary.
@@ skipping 213 matching lines @@
   base::WeakPtrFactory<BalloonCollectionImpl> reposition_factory_;
 
   // Is the balloon collection currently listening for UI events?
   bool added_as_message_loop_observer_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(BalloonCollectionImpl);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_BALLOON_COLLECTION_IMPL_H_