Print preview page selection should not require a rerendering of draft pages.

chrome/renderer/print_web_view_helper_linux.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/file_descriptor_posix.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "chrome/common/print_messages.h"
 #include "content/common/view_messages.h"
 #include "printing/metafile.h"
 #include "printing/metafile_impl.h"
 #include "printing/metafile_skia_wrapper.h"
 #include "skia/ext/vector_canvas.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "ui/gfx/point.h"
 
 #if !defined(OS_CHROMEOS)
 #include "base/process_util.h"
 #endif  // !defined(OS_CHROMEOS)
 
 using WebKit::WebFrame;
 using WebKit::WebNode;
 
 void PrintWebViewHelper::RenderPreviewPage(int page_number) {
+  // printf("Render PP :%d \n", page_number);
   PrintMsg_PrintPage_Params page_params;
   page_params.params = print_preview_context_.print_params();
   page_params.page_number = page_number;
   page_params.page_slot =
       print_preview_context_.GetPageSlotForPage(page_number);
+  printing::Metafile* initial_render_metafile =
+      is_complete_metafile_already_sent_ ? new printing::PreviewMetafile() :
+                                           print_preview_context_.metafile();
 
   base::TimeTicks begin_time = base::TimeTicks::Now();
   PrintPageInternal(page_params,
                     print_preview_context_.GetPrintCanvasSize(),
-                    print_preview_context_.frame(),
-                    print_preview_context_.metafile());
-
+                    print_preview_context_.frame(), initial_render_metafile);
   print_preview_context_.RenderedPreviewPage(
       base::TimeTicks::Now() - begin_time);
   printing::Metafile* page_metafile = NULL;
   if (print_preview_context_.IsModifiable()) {
     page_metafile = reinterpret_cast<printing::PreviewMetafile*>(
-        print_preview_context_.metafile())->GetMetafileForCurrentPage();
+        initial_render_metafile)->GetMetafileForCurrentPage();
+  } else {
+    /* page_metafile = new printing::PreviewMetafile;
+    if (!page_metafile->Init())
+      return;
+    {
+      PrintMsg_Print_Params print_params = print_pages_params_->params;
+      scoped_ptr<PrepareFrameAndViewForPrint> prepare(
+          new PrepareFrameAndViewForPrint(print_params,
+                                          print_preview_context_.frame(),
+                                          print_preview_context_.node()));
+      PrintPageInternal(page_params,
+                        print_preview_context_.GetPrintCanvasSize(),
+                        print_preview_context_.frame(), page_metafile);
+    }
+    page_metafile->FinishDocument(); */
   }
   PreviewPageRendered(page_number, page_metafile);
 }
 
 bool PrintWebViewHelper::PrintPages(const PrintMsg_PrintPages_Params& params,
                                     WebFrame* frame,
                                     WebNode* node,
                                     PrepareFrameAndViewForPrint* prepare) {
   printing::NativeMetafile metafile;
   if (!metafile.Init())
@@ skipping 155 matching lines @@
   canvas->unref();  // SkRefPtr and new both took a reference.
   printing::MetafileSkiaWrapper::SetMetafileOnCanvas(canvas.get(), metafile);
   frame->printPage(params.page_number, canvas.get());
 
   // TODO(myhuang): We should render the header and the footer.
 
   // Done printing. Close the device context to retrieve the compiled metafile.
   if (!metafile->FinishPage())
     NOTREACHED() << "metafile failed";
 }