Eliminate ash::internal namespace

ash/drag_drop/drag_drop_controller.h

Index: ash/drag_drop/drag_drop_controller.h
diff --git a/ash/drag_drop/drag_drop_controller.h b/ash/drag_drop/drag_drop_controller.h
index 5d05ec9445b96e83506c328bfa85c0de2180ab8a..7f20401b25127bd58b49bed82aa5a643c4682b15 100644
--- a/ash/drag_drop/drag_drop_controller.h
+++ b/ash/drag_drop/drag_drop_controller.h
@@ -21,17 +21,14 @@ class LinearAnimation;
 }
 
 namespace ash {
+class DragDropTracker;
+class DragDropTrackerDelegate;
+class DragImageView;
 
 namespace test {
 class DragDropControllerTest;
 }
 
-namespace internal {
-
-class DragDropTracker;
-class DragDropTrackerDelegate;
-class DragImageView;
-
 class ASH_EXPORT DragDropController
     : public aura::client::DragDropClient,
       public ui::EventHandler,
@@ -122,7 +119,7 @@ class ASH_EXPORT DragDropController
   // Closure for quitting nested message loop.
   base::Closure quit_closure_;
 
-  scoped_ptr<ash::internal::DragDropTracker> drag_drop_tracker_;
+  scoped_ptr<ash::DragDropTracker> drag_drop_tracker_;
   scoped_ptr<DragDropTrackerDelegate> drag_drop_window_delegate_;
 
   ui::DragDropTypes::DragEventSource current_drag_event_source_;
@@ -136,7 +133,6 @@ class ASH_EXPORT DragDropController
   DISALLOW_COPY_AND_ASSIGN(DragDropController);
 };
 
-}  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_DRAG_DROP_DRAG_DROP_CONTROLLER_H_