Move GetCursor() method from WindowDelegate to its own delegate interface CursorDelegate.

ash/drag_drop/drag_drop_controller.cc

 // 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.
 
 #include "ash/drag_drop/drag_drop_controller.h"
 
 #include "ash/drag_drop/drag_drop_tracker.h"
 #include "ash/drag_drop/drag_image_view.h"
 #include "ash/shell.h"
 #include "ash/wm/coordinate_conversion.h"
@@ skipping 77 matching lines @@
   virtual gfx::Size GetMinimumSize() const OVERRIDE {
     return gfx::Size();
   }
 
   virtual gfx::Size GetMaximumSize() const OVERRIDE {
     return gfx::Size();
   }
 
   virtual void OnBoundsChanged(const gfx::Rect& old_bounds,
                                const gfx::Rect& new_bounds) OVERRIDE {}
-  virtual gfx::NativeCursor GetCursor(const gfx::Point& point) OVERRIDE {
-    return gfx::kNullCursor;
-  }
   virtual int GetNonClientComponent(const gfx::Point& point) const OVERRIDE {
     return HTCAPTION;
   }
   virtual bool ShouldDescendIntoChildForEventHandling(
       aura::Window* child,
       const gfx::Point& location) OVERRIDE {
     return true;
   }
   virtual bool CanFocus() OVERRIDE { return true; }
   virtual void OnCaptureLost() OVERRIDE {
@@ skipping 446 matching lines @@
     drag_window_->RemoveObserver(this);
   drag_window_ = NULL;
   drag_data_ = NULL;
   // Cleanup can be called again while deleting DragDropTracker, so use Pass
   // instead of reset to avoid double free.
   drag_drop_tracker_.Pass();
 }
 
 }  // namespace internal
 }  // namespace ash