Fixes possible use after free in SessionService

chrome/browser/sessions/base_session_service.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_SESSIONS_BASE_SESSION_SERVICE_H_
 #define CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
@@ skipping 138 matching lines @@
 
   // Invokes SessionBackend::ReadLastSessionCommands with callback on the
   // backend thread.
   // If testing, SessionBackend::ReadLastSessionCommands is invoked directly.
   base::CancelableTaskTracker::TaskId ScheduleGetLastSessionCommands(
       const InternalGetCommandsCallback& callback,
       base::CancelableTaskTracker* tracker);
 
   // This posts the task to the SequencedWorkerPool, or run immediately
   // if the SequencedWorkerPool has been shutdown.
-  bool RunTaskOnBackendThread(const tracked_objects::Location& from_here,
+  void RunTaskOnBackendThread(const tracked_objects::Location& from_here,
                               const base::Closure& task);
 
   // Max number of navigation entries in each direction we'll persist.
   static const int max_persist_navigation_count;
 
  private:
   friend class BetterSessionRestoreCrashTest;
 
   // The profile. This may be null during testing.
   Profile* profile_;
@@ skipping 14 matching lines @@
   // The number of commands sent to the backend before doing a reset.
   int commands_since_reset_;
 
   // A token to make sure that all tasks will be serialized.
   base::SequencedWorkerPool::SequenceToken sequence_token_;
 
   DISALLOW_COPY_AND_ASSIGN(BaseSessionService);
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_BASE_SESSION_SERVICE_H_