Print Preview: Associating preview requests and responses using an identifier

chrome/renderer/print_web_view_helper_mac.mm

 // 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"
 
 #import <AppKit/AppKit.h>
 
 #include "base/logging.h"
 #include "base/mac/scoped_nsautorelease_pool.h"
@@ skipping 109 matching lines @@
                                    preview_page_count_,
                                    render_time,
                                    base::TimeTicks::Now() - begin_time);
 
   PrintHostMsg_DidPreviewDocument_Params preview_params;
   preview_params.reuse_existing_data = false;
   preview_params.data_size = metafile.GetDataSize();
   preview_params.document_cookie = params.params.document_cookie;
   preview_params.expected_pages_count = preview_page_count_;
   preview_params.modifiable = IsModifiable(frame, node);
+  preview_params.preview_request_id = params.params.preview_request_id;
 
   // Ask the browser to create the shared memory for us.
   if (!CopyMetafileDataToSharedMem(&metafile,
                                    &(preview_params.metafile_data_handle))) {
     return false;
   }
   Send(new PrintHostMsg_PagesReadyForPreview(routing_id(), preview_params));
   return true;
 }
 
@@ skipping 22 matching lines @@
     base::mac::ScopedNSAutoreleasePool pool;
     CGContextRef cgContext = metafile->context();
     CGContextRef canvasPtr = cgContext;
 #endif
     frame->printPage(page_number, canvasPtr);
   }
 
   // Done printing. Close the device context to retrieve the compiled metafile.
   metafile->FinishPage();
 }