Thread::Stop() must be called before any subclass's destructor completes.

chrome/default_plugin/plugin_install_job_monitor.cc

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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.
 
 #include "chrome/default_plugin/plugin_install_job_monitor.h"
 
 #include "base/message_loop.h"
 #include "chrome/default_plugin/plugin_impl.h"
 
 PluginInstallationJobMonitorThread::PluginInstallationJobMonitorThread()
     : Thread("Chrome plugin install thread"),
       install_job_completion_port_(NULL),
       stop_job_monitoring_(false),
       plugin_window_(NULL),
       install_job_(NULL) {
 }
 
 PluginInstallationJobMonitorThread::~PluginInstallationJobMonitorThread() {
+  // The way this class is used, Thread::Stop() has always been called
+  // by the time we reach this point, so we do not need to call it
+  // again.
+  DCHECK(!Thread::IsRunning());
   if (install_job_) {
     ::CloseHandle(install_job_);
     install_job_ = NULL;
   }
 }
 
 bool PluginInstallationJobMonitorThread::Initialize() {
   DCHECK(install_job_ == NULL);
 
   install_job_ = ::CreateJobObject(NULL, NULL);
@@ skipping 68 matching lines @@
   Thread::Stop();
   ::CloseHandle(install_job_completion_port_);
   install_job_completion_port_ = NULL;
 }
 
 bool PluginInstallationJobMonitorThread::AssignProcessToJob(
     HANDLE process_handle) {
   BOOL result = AssignProcessToJobObject(install_job_, process_handle);
   return result ? true : false;
 }