Cleanup: Remove forward declarations in various chrome/browser directories.

chrome/browser/printing/print_view_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_PRINTING_PRINT_VIEW_MANAGER_H_
 #define CHROME_BROWSER_PRINTING_PRINT_VIEW_MANAGER_H_
 #pragma once
 
 #include "base/memory/ref_counted.h"
 #include "base/string16.h"
 #include "content/browser/tab_contents/tab_contents_observer.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "printing/printed_pages_source.h"
 
-class RenderViewHost;
 class TabContentsWrapper;
 struct PrintHostMsg_DidPrintPage_Params;
 
 namespace printing {
 
 class JobEventDetails;
 class PrintJob;
 class PrintJobWorkerOwner;
 class PrintViewManagerObserver;
 
@@ skipping 151 matching lines @@
 
   // The document cookie of the current PrinterQuery.
   int cookie_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintViewManager);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_PRINT_VIEW_MANAGER_H_