Cleanup some forward declared structs that are not being used.

chrome/browser/tab_contents/web_contents_view.h

 // Copyright (c) 2006-2008 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_TAB_CONTENTS_WEB_CONTENTS_VIEW_H_
 #define CHROME_BROWSER_TAB_CONTENTS_WEB_CONTENTS_VIEW_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/gfx/native_widget_types.h"
 #include "base/gfx/rect.h"
 #include "base/gfx/size.h"
 #include "chrome/browser/renderer_host/render_view_host_delegate.h"
 
 class Browser;
 class RenderViewHost;
 class RenderWidgetHost;
 class RenderWidgetHostView;
 class WebContents;
-struct WebDropData;
 class WebKeyboardEvent;
 
 namespace base {
 class WaitableEvent;
 }
 
 // The WebContentsView is an interface that is implemented by the platform-
 // dependent web contents views. The WebContents uses this interface to talk to
 // them. View-related messages will also get forwarded directly to this class
 // from RenderViewHost via RenderViewHostDelegate::View.
@@ skipping 159 matching lines @@
 
   // These maps hold on to the widgets that we created on behalf of the
   // renderer that haven't shown yet.
   typedef std::map<int, RenderWidgetHostView*> PendingWidgetViews;
   PendingWidgetViews pending_widget_views_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsView);
 };
 
 #endif  // CHROME_BROWSER_TAB_CONTENTS_WEB_CONTENTS_VIEW_H_