AppCache: fix a browser crashing bug that can happen during updates.

content/browser/appcache/appcache_update_job.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 CONTENT_BROWSER_APPCACHE_APPCACHE_UPDATE_JOB_H_
 #define CONTENT_BROWSER_APPCACHE_APPCACHE_UPDATE_JOB_H_
 
 #include <deque>
 #include <map>
 #include <set>
@@ skipping 265 matching lines @@
 
   AppCacheGroup* group_;
 
   UpdateType update_type_;
   InternalUpdateState internal_state_;
   base::Time last_progress_time_;
   bool doing_full_update_check_;
 
   PendingMasters pending_master_entries_;
   size_t master_entries_completed_;
+  std::set<GURL> failed_master_entries_;
 
   // TODO(jennb): Delete when update no longer fetches master entries directly.
   // Helper containers to track which pending master entries have yet to be
   // fetched and which are currently being fetched. Master entries that
   // are listed in the manifest may be fetched as a regular URL instead of
   // as a separate master entry fetch to optimize against duplicate fetches.
   std::set<GURL> master_entries_to_fetch_;
   PendingUrlFetches master_entry_fetches_;
 
   // URLs of files to fetch along with their flags.
@@ skipping 44 matching lines @@
   base::WeakPtrFactory<AppCacheUpdateJob> weak_factory_;
 
   FRIEND_TEST_ALL_PREFIXES(content::AppCacheGroupTest, QueueUpdate);
 
   DISALLOW_COPY_AND_ASSIGN(AppCacheUpdateJob);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_APPCACHE_APPCACHE_UPDATE_JOB_H_