Cleanup: Remove unneeded forward declarations from chrome/browser/extensions.

chrome/browser/extensions/extension_process_manager.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 CHROME_BROWSER_EXTENSIONS_EXTENSION_PROCESS_MANAGER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_PROCESS_MANAGER_H_
 #pragma once
 
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "content/public/common/view_types.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class Browser;
 class BrowsingInstance;
 class Extension;
 class ExtensionHost;
 class GURL;
 class Profile;
-class RenderProcessHost;
 class RenderViewHost;
 class SiteInstance;
 
 // Manages dynamic state of running Chromium extensions. There is one instance
 // of this class per Profile. OTR Profiles have a separate instance that keeps
 // track of split-mode extensions only.
 class ExtensionProcessManager : public content::NotificationObserver {
  public:
   static ExtensionProcessManager* Create(Profile* profile);
   virtual ~ExtensionProcessManager();
@@ skipping 94 matching lines @@
   // Close the given |host| iff it's a background page.
   void CloseBackgroundHost(ExtensionHost* host);
 
   // Excludes background page.
   bool HasVisibleViews(const std::string& extension_id);
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionProcessManager);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_PROCESS_MANAGER_H_