Notify print preview UI if getting capabilityes failed.

chrome/browser/ui/webui/print_preview/print_preview_handler.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
@@ skipping 143 matching lines @@
   void HandleReportDestinationEvent(const base::ListValue* args);
 
   void SendInitialSettings(
       const std::string& default_printer,
       const std::string& cloud_print_data);
 
   // Sends the printer capabilities to the Web UI. |settings_info| contains
   // printer capabilities information.
   void SendPrinterCapabilities(const base::DictionaryValue& settings_info);
 
+  // Sends error notification to the Web UI when unable to return the printer
+  // capabilities.
+  void SendFailedToGetPrinterCapabilities(const std::string& printer_name);
+
   // Send the list of printers to the Web UI.
   void SetupPrinterList(const base::ListValue& printers);
 
   // Send whether cloud print integration should be enabled.
   void SendCloudPrintEnabled();
 
   // Send the PDF data to the cloud to print.
   void SendCloudPrintJob(const base::DictionaryValue& settings,
                          std::string print_ticket);
 
@@ skipping 38 matching lines @@
   bool has_logged_printers_count_;
 
   // Holds the path to the print to pdf request. It is empty if no such request
   // exists.
   scoped_ptr<FilePath> print_to_pdf_path_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewHandler);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_