Extract minimal RenderViewHost interface for embedders, leaving

content/browser/tab_contents/web_drag_dest_gtk.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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 CONTENT_BROWSER_TAB_CONTENTS_WEB_DRAG_DEST_GTK_H_
 #define CONTENT_BROWSER_TAB_CONTENTS_WEB_DRAG_DEST_GTK_H_
 #pragma once
 
 #include <gtk/gtk.h>
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "content/common/content_export.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
 #include "ui/base/gtk/gtk_signal.h"
 #include "webkit/glue/webdropdata.h"
 
+class RenderViewHostImpl;
+
 namespace content {
 
 class WebContents;
 class WebDragDestDelegate;
 
 // A helper class that handles DnD for drops in the renderer. In GTK parlance,
 // this handles destination-side DnD, but not source-side DnD.
 class CONTENT_EXPORT WebDragDestGtk {
  public:
   WebDragDestGtk(WebContents* web_contents, GtkWidget* widget);
   ~WebDragDestGtk();
 
   // This is called when the renderer responds to a drag motion event. We must
   // update the system drag cursor.
   void UpdateDragStatus(WebKit::WebDragOperation operation);
 
   // Informs the renderer when a system drag has left the render view.
   // See OnDragLeave().
   void DragLeave();
 
   WebDragDestDelegate* delegate() const { return delegate_; }
   void set_delegate(WebDragDestDelegate* delegate) { delegate_ = delegate; }
 
  private:
+  RenderViewHostImpl* GetRenderViewHost() const;
+
   // Called when a system drag crosses over the render view. As there is no drag
   // enter event, we treat it as an enter event (and not a regular motion event)
   // when |context_| is NULL.
   CHROMEGTK_CALLBACK_4(WebDragDestGtk, gboolean, OnDragMotion, GdkDragContext*,
                        gint, gint, guint);
 
   // We make a series of requests for the drag data when the drag first enters
   // the render view. This is the callback that is used to give us the data
   // for each individual target. When |data_requests_| reaches 0, we know we
   // have attained all the data, and we can finally tell the renderer about the
@@ skipping 43 matching lines @@
   WebDragDestDelegate* delegate_;
 
   base::WeakPtrFactory<WebDragDestGtk> method_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebDragDestGtk);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_TAB_CONTENTS_WEB_DRAG_DEST_GTK_H_