Extract minimal RenderViewHost interface for embedders, leaving

content/browser/tab_contents/web_drag_source_gtk.h

Index: content/browser/tab_contents/web_drag_source_gtk.h
diff --git a/content/browser/tab_contents/web_drag_source_gtk.h b/content/browser/tab_contents/web_drag_source_gtk.h
index 55b4f742995ad2d32b3d0554758aacc0172822d4..83ea99dea26fdb769d7799a07cfa306560da82d2 100644
--- a/content/browser/tab_contents/web_drag_source_gtk.h
+++ b/content/browser/tab_contents/web_drag_source_gtk.h
@@ -1,4 +1,4 @@
-// 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.
 
@@ -20,6 +20,7 @@
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/point.h"
 
+class RenderViewHostImpl;
 class SkBitmap;
 struct WebDropData;
 
@@ -58,6 +59,7 @@ class CONTENT_EXPORT WebDragSourceGtk : public MessageLoopForUI::Observer {
   CHROMEGTK_CALLBACK_1(WebDragSourceGtk, gboolean, OnDragIconExpose,
                        GdkEventExpose*);
 
+  RenderViewHostImpl* GetRenderViewHost() const;
   gfx::NativeView GetContentNativeView() const;
 
   // The tab we're manging the drag for.