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

ash/drag_drop/drag_drop_controller.cc

Index: ash/drag_drop/drag_drop_controller.cc
diff --git a/ash/drag_drop/drag_drop_controller.cc b/ash/drag_drop/drag_drop_controller.cc
index 15429c80982d3289a851c29c08808292dd2609b8..4df5f713aa922d59ffabdb39cd2cda25745817bb 100644
--- a/ash/drag_drop/drag_drop_controller.cc
+++ b/ash/drag_drop/drag_drop_controller.cc
@@ -95,6 +95,9 @@
 
   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;
   }