Get drag and drop working for win aura.

ui/views/widget/desktop_aura/desktop_native_widget_aura.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.
 
 #ifndef UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_NATIVE_WIDGET_AURA_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_NATIVE_WIDGET_AURA_H_
 
 #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"
 
 namespace aura {
 class RootWindow;
 namespace client {
 class StackingClient;
 }
 }
 
 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();
 
   // Maps from window to DesktopNativeWidgetAura.
   static DesktopNativeWidgetAura* ForWindow(aura::Window* window);
 
   // Called by our DesktopRootWindowHost after it has deleted native resources;
   // this is the signal that we should start our shutdown.
   void OnHostClosed();
@@ skipping 113 matching lines @@
   virtual ui::EventResult OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual ui::EventResult OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
   virtual ui::EventResult OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
   virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // Overridden from aura::client::ActivationDelegate:
   virtual bool ShouldActivate() const OVERRIDE;
   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_;
 
   // The NativeWidget owns the RootWindow. Required because the RootWindow owns
   // its RootWindowHost, so DesktopRootWindowHost can't own it.
   scoped_ptr<aura::RootWindow> root_window_;
 
   // The following factory is used for calls to close the NativeWidgetAura
   // instance.
   base::WeakPtrFactory<DesktopNativeWidgetAura> close_widget_factory_;
 
   scoped_ptr<NativeWidgetAuraWindowObserver> active_window_observer_;
 
   // Can we be made active?
   bool can_activate_;
 
   // Ownership passed to RootWindow on Init.
   DesktopRootWindowHost* desktop_root_window_host_;
   aura::Window* window_;
   internal::NativeWidgetDelegate* native_widget_delegate_;
 
   scoped_ptr<aura::client::StackingClient> stacking_client_;
 
+  scoped_ptr<DropHelper> drop_helper_;
+  int last_drop_operation_;
+
   DISALLOW_COPY_AND_ASSIGN(DesktopNativeWidgetAura);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_NATIVE_WIDGET_AURA_H_