Fixes possible use after free in SessionService

chrome/browser/sessions/base_session_service.cc

 // 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.
 
 #include "chrome/browser/sessions/base_session_service.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/pickle.h"
 #include "base/stl_util.h"
@@ skipping 276 matching lines @@
       base::Bind(&PostOrRunInternalGetCommandsCallback,
                  base::MessageLoopProxy::current(), run_if_not_canceled);
 
   RunTaskOnBackendThread(
       FROM_HERE,
       base::Bind(&SessionBackend::ReadLastSessionCommands, backend(),
                  is_canceled, callback_runner));
   return id;
 }
 
-bool BaseSessionService::RunTaskOnBackendThread(
+void BaseSessionService::RunTaskOnBackendThread(
     const tracked_objects::Location& from_here,
     const base::Closure& task) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   base::SequencedWorkerPool* pool = content::BrowserThread::GetBlockingPool();
   if (!pool->IsShutdownInProgress()) {
-    return pool->PostSequencedWorkerTask(sequence_token_,
-                                         from_here,
-                                         task);
+    pool->PostSequencedWorkerTask(sequence_token_, from_here, task);
   } else {
     // Fall back to executing on the main thread if the sequence
     // worker pool has been requested to shutdown (around shutdown
     // time).
     task.Run();
-    return true;
   }
 }