Get drag and drop working for win aura.

ui/views/widget/desktop_aura/desktop_native_widget_aura.h

Index: ui/views/widget/desktop_aura/desktop_native_widget_aura.h
===================================================================
--- ui/views/widget/desktop_aura/desktop_native_widget_aura.h	(revision 171535)
+++ ui/views/widget/desktop_aura/desktop_native_widget_aura.h	(working copy)
@@ -7,6 +7,7 @@
 
 #include "base/memory/weak_ptr.h"
 #include "ui/aura/client/activation_delegate.h"
+#include "ui/aura/client/drag_drop_delegate.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/views/widget/native_widget_private.h"
 
@@ -20,13 +21,15 @@
 namespace views {
 
 class DesktopRootWindowHost;
+class DropHelper;
 class NativeWidgetAuraWindowObserver;
 
 // TODO(erg): May also need to be a DragDropDelegate
 class VIEWS_EXPORT DesktopNativeWidgetAura
     : public internal::NativeWidgetPrivate,
       public aura::WindowDelegate,
-      public aura::client::ActivationDelegate {
+      public aura::client::ActivationDelegate,
+      public aura::client::DragDropDelegate {
  public:
   explicit DesktopNativeWidgetAura(internal::NativeWidgetDelegate* delegate);
   virtual ~DesktopNativeWidgetAura();
@@ -160,6 +163,12 @@
   virtual void OnActivated() OVERRIDE;
   virtual void OnLostActive() OVERRIDE;
 
+  // Overridden from aura::client::DragDropDelegate:
+  virtual void OnDragEntered(const ui::DropTargetEvent& event) OVERRIDE;
+  virtual int OnDragUpdated(const ui::DropTargetEvent& event) OVERRIDE;
+  virtual void OnDragExited() OVERRIDE;
+  virtual int OnPerformDrop(const ui::DropTargetEvent& event) OVERRIDE;
+
  private:
   // See class documentation for Widget in widget.h for a note about ownership.
   Widget::InitParams::Ownership ownership_;
@@ -184,6 +193,9 @@
 
   scoped_ptr<aura::client::StackingClient> stacking_client_;
 
+  scoped_ptr<DropHelper> drop_helper_;
+  int last_drop_operation_;
+
   DISALLOW_COPY_AND_ASSIGN(DesktopNativeWidgetAura);
 };