Print Preview: Go from event driven print preview back to print preview with sync messages. The s...

chrome/renderer/print_web_view_helper_win.cc

 // 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.
 
 #include "chrome/renderer/print_web_view_helper.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/process_util.h"
@@ skipping 103 matching lines @@
   page_params.has_visible_overlays = frame->isPageBoxVisible(page_number);
 
   if (!CopyMetafileDataToSharedMem(metafile.get(),
                                    &(page_params.metafile_data_handle))) {
     page_params.data_size = 0;
   }
 
   Send(new PrintHostMsg_DidPrintPage(routing_id(), page_params));
 }
 
-void PrintWebViewHelper::RenderPreviewPage(int page_number) {
+bool PrintWebViewHelper::RenderPreviewPage(int page_number) {
   PrintMsg_Print_Params print_params = print_preview_context_.print_params();
   // Calculate the dpi adjustment.
   float scale_factor = static_cast<float>(print_params.desired_dpi /
                                           print_params.dpi);
 
   base::TimeTicks begin_time = base::TimeTicks::Now();
   printing::Metafile* render_page_result =
       RenderPage(print_params, &scale_factor, page_number, true,
                  print_preview_context_.frame(),
                  print_preview_context_.metafile());
   // In the preview flow, RenderPage will never return a new metafile.
   DCHECK_EQ(render_page_result, print_preview_context_.metafile());
 
   print_preview_context_.RenderedPreviewPage(
       base::TimeTicks::Now() - begin_time);
 
   scoped_ptr<printing::Metafile> page_metafile;
   if (print_preview_context_.IsModifiable()) {
     page_metafile.reset(
         print_preview_context_.metafile()->GetMetafileForCurrentPage());
   }
-  PreviewPageRendered(page_number, page_metafile.get());
+  return PreviewPageRendered(page_number, page_metafile.get());
 }
 
 Metafile* PrintWebViewHelper::RenderPage(
     const PrintMsg_Print_Params& params, float* scale_factor, int page_number,
     bool is_preview, WebFrame* frame, Metafile* metafile) {
   PageSizeMargins page_layout_in_points;
   GetPageSizeAndMarginsInPoints(frame, page_number, params,
                                 &page_layout_in_points);
 
   int width;
@@ skipping 130 matching lines @@
     shared_buf.Unmap();
     return false;
   }
   shared_buf.GiveToProcess(base::GetCurrentProcessHandle(), shared_mem_handle);
   shared_buf.Unmap();
 
   Send(new PrintHostMsg_DuplicateSection(routing_id(), *shared_mem_handle,
                                          shared_mem_handle));
   return true;
 }