Print Preview: Associating preview requests and responses using an identifier

chrome/renderer/print_web_view_helper.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 <string>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 364 matching lines @@
   if (old_print_pages_params_.get() &&
       PrintMsg_Print_Params_IsEqual(*old_print_pages_params_,
                                     *print_pages_params_)) {
     PrintHostMsg_DidPreviewDocument_Params preview_params;
     preview_params.reuse_existing_data = true;
     preview_params.data_size = 0;
     preview_params.document_cookie =
         print_pages_params_->params.document_cookie;
     preview_params.expected_pages_count = preview_page_count_;
     preview_params.modifiable = IsModifiable(frame, node);
+    preview_params.preview_request_id =
+        print_pages_params_->params.preview_request_id;
 
     Send(new PrintHostMsg_PagesReadyForPreview(routing_id(), preview_params));
     return;
   }
 
   // Render Pages for preview.
   if (!RenderPagesForPreview(frame, node))
     DidFinishPrinting(FAIL_PREVIEW);
 }
 
@@ skipping 284 matching lines @@
 bool PrintWebViewHelper::UpdatePrintSettingsLocal(
     const DictionaryValue& job_settings) {
   PrintMsg_PrintPages_Params settings;
 
   Send(new PrintHostMsg_UpdatePrintSettings(routing_id(),
       print_pages_params_->params.document_cookie, job_settings, &settings));
 
   if (settings.params.dpi < kMinDpi || !settings.params.document_cookie)
     return false;
 
+  if (!job_settings.GetInteger(printing::kPreviewRequestID,
+                               &settings.params.preview_request_id)) {
+    NOTREACHED();
+    return false;
+  }
+
   print_pages_params_.reset(new PrintMsg_PrintPages_Params(settings));
   Send(new PrintHostMsg_DidGetDocumentCookie(routing_id(),
                                              settings.params.document_cookie));
   return true;
 }
 
 bool PrintWebViewHelper::UpdatePrintSettings(
     const DictionaryValue& job_settings) {
   if (job_settings.HasKey(printing::kSettingCloudPrintId)) {
     return UpdatePrintSettingsCloud(job_settings);
@@ skipping 157 matching lines @@
   Send(new PrintHostMsg_RequestPrintPreview(routing_id()));
 }
 
 bool PrintWebViewHelper::PreviewPageRendered(int page_number) {
   bool cancel = false;
   Send(new PrintHostMsg_DidPreviewPage(routing_id(), page_number, &cancel));
   if (cancel)
     notify_browser_of_print_failure_ = false;
   return !cancel;
 }