Add skia::RefPtr class to wrap ref counted classes from Skia.

chrome/renderer/print_web_view_helper_linux.cc

 // 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.
 
 #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"
@@ skipping 176 matching lines @@
   gfx::Rect canvas_area =
       params.params.display_header_footer ? gfx::Rect(page_size) : content_area;
 
   SkDevice* device = metafile->StartPageForVectorCanvas(page_size, canvas_area,
                                                         scale_factor);
   if (!device)
     return;
 
   // The printPage method take a reference to the canvas we pass down, so it
   // can't be a stack object.
-  SkRefPtr<skia::VectorCanvas> canvas = new skia::VectorCanvas(device);
-  canvas->unref();  // SkRefPtr and new both took a reference.
+  skia::RefPtr<skia::VectorCanvas> canvas =
+      skia::AdoptRef(new skia::VectorCanvas(device));
   printing::MetafileSkiaWrapper::SetMetafileOnCanvas(*canvas, metafile);
   skia::SetIsDraftMode(*canvas, is_print_ready_metafile_sent_);
 
   if (params.params.display_header_footer) {
     // |page_number| is 0-based, so 1 is added.
     // TODO(vitalybuka) : why does it work only with 1.25?
     PrintHeaderAndFooter(canvas.get(), params.page_number + 1,
                          print_preview_context_.total_page_count(),
                          scale_factor / 1.25,
                          page_layout_in_points, *header_footer_info_,
                          params.params);
   }
   RenderPageContent(frame, params.page_number, canvas_area, content_area,
                     scale_factor, canvas.get());
 
   // Done printing. Close the device context to retrieve the compiled metafile.
   if (!metafile->FinishPage())
     NOTREACHED() << "metafile failed";
 }