Moved the following IPC messages used by the chrome NPAPI plugin installer out of content

content/plugin/webplugin_delegate_stub.h

 // Copyright (c) 2011 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_PLUGIN_WEBPLUGIN_DELEGATE_STUB_H_
 #define CONTENT_PLUGIN_WEBPLUGIN_DELEGATE_STUB_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 79 matching lines @@
                             const gfx::Rect& view_frame);
   void OnImeCompositionCompleted(const string16& text);
 #endif
 
   void OnDidReceiveManualResponse(
       const GURL& url,
       const PluginMsg_DidReceiveResponseParams& params);
   void OnDidReceiveManualData(const std::vector<char>& buffer);
   void OnDidFinishManualLoading();
   void OnDidManualLoadFail();
-  void OnInstallMissingPlugin();
   void OnHandleURLRequestReply(unsigned long resource_id,
                                const GURL& url,
                                int notify_id);
   void OnHTTPRangeRequestReply(unsigned long resource_id, int range_request_id);
 
   std::string mime_type_;
   int instance_id_;
 
   scoped_refptr<PluginChannel> channel_;
 
@@ skipping 10 matching lines @@
   // window handle which is used for subsequent communication back to the
   // browser.
   void OnSetFakeAcceleratedSurfaceWindowHandle(gfx::PluginWindowHandle window);
 #endif
 #endif
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(WebPluginDelegateStub);
 };
 
 #endif  // CONTENT_PLUGIN_WEBPLUGIN_DELEGATE_STUB_H_