Plumb the DragOperation through all the layers between the platform DnD code ...

chrome/browser/renderer_host/render_view_host_delegate.h

 // Copyright (c) 2009 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 CHROME_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 #define CHROME_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/string16.h"
 #include "chrome/common/view_types.h"
 #include "net/base/load_states.h"
+#include "webkit/api/public/WebDragOperation.h"
 #include "webkit/glue/window_open_disposition.h"
 
 class AutofillForm;
 struct ContextMenuParams;
 class FilePath;
 class GURL;
 struct NativeWebKeyboardEvent;
 class NavigationEntry;
 class Profile;
 struct RendererPreferences;
@@ skipping 79 matching lines @@
     virtual void ShowCreatedWidget(int route_id,
                                    const gfx::Rect& initial_pos) = 0;
 
     // A context menu should be shown, to be built using the context information
     // provided in the supplied params.
     virtual void ShowContextMenu(const ContextMenuParams& params) = 0;
 
     // The user started dragging content of the specified type within the
     // RenderView. Contextual information about the dragged content is supplied
     // by WebDropData.
-    virtual void StartDragging(const WebDropData& drop_data) = 0;
+    virtual void StartDragging(const WebDropData& drop_data,
+                               WebKit::WebDragOperationsMask allowed_ops) = 0;
 
     // The page wants to update the mouse cursor during a drag & drop operation.
-    // |is_drop_target| is true if the mouse is over a valid drop target.
-    virtual void UpdateDragCursor(bool is_drop_target) = 0;
+    // |operation| describes the current operation (none, move, copy, link.)
+    virtual void UpdateDragCursor(WebKit::WebDragOperation operation) = 0;
 
     // Notification that view for this delegate got the focus.
     virtual void GotFocus() = 0;
 
     // Callback to inform the browser it should take back focus. If reverse is
     // true, it means the focus was retrieved by doing a Shift-Tab.
     virtual void TakeFocus(bool reverse) = 0;
 
     // Callback to inform the browser that the renderer did not process the
     // specified events. This gives an opportunity to the browser to process the
@@ skipping 409 matching lines @@
   virtual void LoadStateChanged(const GURL& url, net::LoadState load_state) {}
 
   // Returns true if this view is used to host an external tab container.
   virtual bool IsExternalTabContainer() const;
 
   // The RenderView has inserted one css file into page.
   virtual void DidInsertCSS() {}
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_