Create a Factory for NativeMetafile.

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/scoped_ptr.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/render_messages_params.h"
-#include "printing/native_metafile.h"
+#include "printing/metafile_factory.h"
 #include "skia/ext/vector_canvas.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSize.h"
 
-using printing::NativeMetafile;
 using WebKit::WebFrame;
 using WebKit::WebNode;
 using WebKit::WebSize;
 
 void PrintWebViewHelper::PrintPages(const ViewMsg_PrintPages_Params& params,
                                     WebFrame* frame,
                                     WebNode* node) {
   // We only can use PDF in the renderer because Cairo needs to create a
   // temporary file for a PostScript surface.
-  printing::NativeMetafile metafile(printing::NativeMetafile::PDF);
+  scoped_ptr<printing::NativeMetafile> metafile_ptr(
+      printing::MetafileFactory::GetMetafile());
   int page_count;
   skia::VectorCanvas* canvas = NULL;
 
   {
     // Hack - when |prep_frame_view| goes out of scope, PrintEnd() gets called.
     // Doing this before closing |metafile| below ensures
     // webkit::ppapi::PluginInstance::PrintEnd() has a valid canvas/metafile to
     // save the final output to. See pepper_plugin_instance.cc for the whole
     // story.
     ViewMsg_Print_Params printParams = params.params;
     PrepareFrameAndViewForPrint prep_frame_view(printParams,
                                                 frame,
                                                 node,
                                                 frame->view());
     page_count = prep_frame_view.GetExpectedPageCount();
 
     // TODO(myhuang): Send ViewHostMsg_DidGetPrintedPagesCount.
 
     if (page_count == 0)
       return;
 
-    metafile.Init();
+    metafile_ptr->Init();
 
     ViewMsg_PrintPage_Params page_params;
     page_params.params = printParams;
     const gfx::Size& canvas_size = prep_frame_view.GetPrintCanvasSize();
     if (params.pages.empty()) {
       for (int i = 0; i < page_count; ++i) {
         page_params.page_number = i;
         delete canvas;
-        PrintPage(page_params, canvas_size, frame, &metafile, &canvas);
+        PrintPage(page_params, canvas_size, frame, metafile_ptr.get(), &canvas);
       }
     } else {
       for (size_t i = 0; i < params.pages.size(); ++i) {
         page_params.page_number = params.pages[i];
         delete canvas;
-        PrintPage(page_params, canvas_size, frame, &metafile, &canvas);
+        PrintPage(page_params, canvas_size, frame, metafile_ptr.get(), &canvas);
       }
     }
   }
 
   delete canvas;
-  metafile.Close();
+  metafile_ptr->Close();
 
   int sequence_number = -1;
   // Get the size of the resulting metafile.
-  uint32 buf_size = metafile.GetDataSize();
+  uint32 buf_size = metafile_ptr->GetDataSize();
   DCHECK_GT(buf_size, 0u);
 
   base::FileDescriptor fd;
 
   // Ask the browser to open a file for us.
   if (!Send(new ViewHostMsg_AllocateTempFileForPrinting(&fd,
                                                         &sequence_number))) {
     return;
   }
 
-  if (!metafile.SaveTo(fd))
+  if (!metafile_ptr->SaveTo(fd))
     return;
 
   // Tell the browser we've finished writing the file.
   Send(new ViewHostMsg_TempFileForPrintingWritten(sequence_number));
 }
 
 void PrintWebViewHelper::PrintPage(const ViewMsg_PrintPage_Params& params,
                                    const gfx::Size& canvas_size,
                                    WebFrame* frame,
                                    printing::NativeMetafile* metafile,
@@ skipping 29 matching lines @@
                                    canvas_size.height());
   frame->printPage(params.page_number, *canvas);
 
   // TODO(myhuang): We should handle transformation for paper margins.
   // 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";
 }