ash uber tray: Fix a couple of crashes when quitting.

ash/system/tray/system_tray.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 "ash/system/tray/system_tray.h"
 
 #include "ash/shell/panel_window.h"
 #include "ash/system/tray/system_tray_item.h"
 #include "ash/wm/shadow_types.h"
 #include "base/logging.h"
@@ skipping 63 matching lines @@
 namespace ash {
 
 SystemTray::SystemTray()
     : items_(),
       popup_(NULL) {
   SetLayoutManager(new views::BoxLayout(views::BoxLayout::kHorizontal,
         5, 10, 3));
 }
 
 SystemTray::~SystemTray() {
+  if (popup_)
+    popup_->CloseNow();
   for (std::vector<SystemTrayItem*>::iterator it = items_.begin();
       it != items_.end();
       ++it) {
     (*it)->DestroyTrayView();
   }
 }
 
 void SystemTray::AddTrayItem(SystemTrayItem* item) {
   items_.push_back(item);
 
@@ skipping 33 matching lines @@
     ShowItems(items_, false);
   return true;
 }
 
 void SystemTray::OnWidgetClosing(views::Widget* widget) {
   CHECK_EQ(popup_, widget);
   popup_ = NULL;
 }
 
 }  // namespace ash