Make printing work for PDF and Flash.

chrome/browser/printing/print_preview_message_handler.h

 // 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.
 
 #ifndef CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_
 #define CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
 
 class PrintPreviewUI;
 struct PrintHostMsg_DidGetPreviewPageCount_Params;
 struct PrintHostMsg_DidPreviewDocument_Params;
 struct PrintHostMsg_DidPreviewPage_Params;
 struct PrintHostMsg_RequestPrintPreview_Params;
 struct PrintHostMsg_SetOptionsFromDocument_Params;
 
 namespace content {
+class RenderFrameHost;
 class WebContents;
 }
 
 namespace gfx {
 class Rect;
 }
 
 namespace printing {
 
 struct PageSizeMargins;
@@ skipping 15 matching lines @@
 
   // Gets the print preview dialog associated with the WebContents being
   // observed.
   content::WebContents* GetPrintPreviewDialog();
 
   // Gets the PrintPreviewUI associated with the WebContents being observed.
   PrintPreviewUI* GetPrintPreviewUI();
 
   // Message handlers.
   void OnRequestPrintPreview(
+      content::RenderFrameHost* render_frame_host,
       const PrintHostMsg_RequestPrintPreview_Params& params);
   void OnDidGetDefaultPageLayout(const PageSizeMargins& page_layout_in_points,
                                  const gfx::Rect& printable_area_in_points,
                                  bool has_custom_page_size_style);
   void OnDidGetPreviewPageCount(
       const PrintHostMsg_DidGetPreviewPageCount_Params& params);
   void OnDidPreviewPage(const PrintHostMsg_DidPreviewPage_Params& params);
   void OnMetafileReadyForPrinting(
       const PrintHostMsg_DidPreviewDocument_Params& params);
   void OnPrintPreviewFailed(int document_cookie);
   void OnPrintPreviewCancelled(int document_cookie);
   void OnInvalidPrinterSettings(int document_cookie);
   void OnSetOptionsFromDocument(
       const PrintHostMsg_SetOptionsFromDocument_Params& params);
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewMessageHandler);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_