Make SharedMemoryHandle a class on windows.

components/printing/renderer/print_web_view_helper_pdf_win.cc

 // Copyright 2014 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 "components/printing/renderer/print_web_view_helper.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/process/process_handle.h"
 #include "components/printing/common/print_messages.h"
@@ skipping 93 matching lines @@
   printed_page_params.data_size = metafile.GetDataSize();
   printed_page_params.document_cookie = params.params.document_cookie;
   printed_page_params.page_size = params.params.page_size;
 
   for (size_t i = 0; i < printed_pages.size(); ++i) {
     printed_page_params.page_number = printed_pages[i];
     printed_page_params.page_size = page_size_in_dpi[i];
     printed_page_params.content_area = content_area_in_dpi[i];
     Send(new PrintHostMsg_DidPrintPage(routing_id(), printed_page_params));
     // Send the rest of the pages with an invalid metafile handle.
-    printed_page_params.metafile_data_handle = nullptr;
+    printed_page_params.metafile_data_handle = base::SharedMemoryHandle();
   }
   return true;
 }
 
 void PrintWebViewHelper::PrintPageInternal(
     const PrintMsg_PrintPage_Params& params,
     WebFrame* frame,
     PdfMetafileSkia* metafile,
     gfx::Size* page_size_in_dpi,
     gfx::Rect* content_area_in_dpi) {
@@ skipping 75 matching lines @@
                                 shared_mem_handle)) {
     return false;
   }
 
   Send(new PrintHostMsg_DuplicateSection(routing_id(), *shared_mem_handle,
                                          shared_mem_handle));
   return true;
 }
 
 }  // namespace printing