Print Preview: Handle a crashed initiator tab by showing a message in PP.

chrome/browser/ui/webui/print_preview_ui.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_UI_H_
 #pragma once
 
 #include <string>
 
@@ skipping 19 matching lines @@
                                    scoped_refptr<RefCountedBytes>* data);
 
   // Sets the print preview |data|. |index| is zero-based, and can be
   // |printing::COMPLETE_PREVIEW_DOCUMENT_INDEX| to set the entire preview
   // document.
   void SetPrintPreviewDataForIndex(int index, const RefCountedBytes* data);
 
   // Clear the existing print preview data.
   void ClearAllPreviewData();
 
+  // Setters
+  void SetInitiatorTabURL(const std::string& initiator_url);
+
   // Notifies the Web UI that there is a print preview request. There should be
   // a matching call to OnPreviewDataIsAvailable() or OnPrintPreviewFailed().
   void OnPrintPreviewRequest();
 
   // Notifies the Web UI about the page count of the request preview.
   void OnDidGetPreviewPageCount(
       const PrintHostMsg_DidGetPreviewPageCount_Params& params);
 
   // Notifies the Web UI that the 0-based page |page_number| has been rendered.
   // |preview_request_id| indicates wich request resulted in this response.
   void OnDidPreviewPage(int page_number, int preview_request_id);
 
   // Notifies the Web UI renderer that preview data is available.
   // |expected_pages_count| specifies the total number of pages. |job_title| is
   // the title of the page being previewed. |preview_request_id| indicates which
   // request resulted in this response.
   void OnPreviewDataIsAvailable(int expected_pages_count,
                                 const string16& job_title,
                                 int preview_request_id);
 
   void OnReusePreviewData(int preview_request_id);
 
-  // Notifies the Web UI that a navigation has occurred in this tab. This is the
-  // last chance to communicate with the source tab before the association is
-  // erased.
-  void OnNavigation();
+  // Notifies the Web UI that preview tab is destroyed. This is the last chance
+  // to communicate with the source tab before the association is erased.
+  void OnTabDestroyed();
 
   // Notifies the Web UI that the print preview failed to render.
   void OnPrintPreviewFailed();
 
   // Notifies the Web UI that the print preview request has been cancelled.
   void OnPrintPreviewCancelled();
 
   // Notifies the Web UI that initiator tab is closed, so we can disable all the
   // controls that need the initiator tab for generating the preview data.
-  void OnInitiatorTabClosed(const std::string& initiator_url);
+  void OnInitiatorTabClosed();
+
+  // Notifies the Web UI that the initiator tab has crashed.
+  void OnInitiatorTabCrashed();
 
   // Notifies the Web UI renderer that file selection has been cancelled.
   void OnFileSelectionCancelled();
 
   // Returns true if there are pending requests.
   bool HasPendingRequests();
 
   int document_cookie();
 
  private:
   // Returns the Singleton instance of the PrintPreviewDataService.
   PrintPreviewDataService* print_preview_data_service();
 
   void DecrementRequestCount();
 
   base::TimeTicks initial_preview_start_time_;
 
   // Store the PrintPreviewUI address string.
   std::string preview_ui_addr_str_;
 
   // Weak pointer to the WebUI handler.
   PrintPreviewHandler* handler_;
 
   // The number of print preview requests in flight.
   uint32 request_count_;
 
   // Document cookie from the initiator renderer.
   int document_cookie_;
 
+  // Store the |initiator_url| in order to display an accurate error message
+  // when the initiator tab is closed/crashed.
+  std::string initiator_url_;
+
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_UI_H_