Refactor win printing workflow to support print preview.

chrome/renderer/print_web_view_helper.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_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #define CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 156 matching lines @@
   bool GetPrintSettingsFromUser(WebKit::WebFrame* frame,
                                 int expected_pages_count,
                                 bool use_browser_overlays);
 
   // Render the frame for printing.
   void RenderPagesForPrint(WebKit::WebFrame* frame,
                            WebKit::WebNode* node);
 
   // Render the frame for preview.
   void RenderPagesForPreview(WebKit::WebFrame* frame);
+
+  // Renders all the pages listed in |params| for preview.
+  // On Success, |preview_params| will have a valid handle to metafile data,
+  // data buffer size and document cookie.
   void CreatePreviewDocument(const ViewMsg_PrintPages_Params& params,
       WebKit::WebFrame* frame,
       ViewHostMsg_DidPreviewDocument_Params* preview_params);
 #if defined(OS_MACOSX)
   void RenderPage(const gfx::Size& page_size, const gfx::Point& content_origin,
                   const float& scale_factor, int page_number,
                   WebKit::WebFrame* frame, printing::NativeMetafile* metafile);
 #elif defined(OS_WIN)
-  void RenderPage(const gfx::Size& page_size, float* scale_factor,
+  void RenderPage(const ViewMsg_Print_Params& params, float* scale_factor,
                   int page_number, WebKit::WebFrame* frame,
-                  scoped_ptr<printing::NativeMetafile>* metafile,
-                  bool supports_alpha_blend);
+                  scoped_ptr<printing::NativeMetafile>* metafile);
 #endif
 
 #if defined(OS_MACOSX) || defined(OS_WIN)
   bool CopyMetafileDataToSharedMem(printing::NativeMetafile* metafile,
       base::SharedMemoryHandle* shared_mem_handle);
 #endif
 
   RenderView* render_view_;
   WebKit::WebView* print_web_view_;
   scoped_ptr<ViewMsg_PrintPages_Params> print_pages_params_;
   base::Time last_cancelled_script_print_;
   int user_cancelled_scripted_print_count_;
   bool is_preview_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(PrintWebViewHelper);
 };
 
 #endif  // CHROME_RENDERER_PRINT_WEB_VIEW_HELPER_H_