aura: Fix a couple of tooltip related bugs:

ash/shell/lock_view.cc

 // 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 "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/shell/example_factory.h"
+#include "ash/tooltips/tooltip_controller.h"
 #include "base/utf_string_conversions.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/font.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 
 using ash::Shell;
 
@@ skipping 43 matching lines @@
                             (root_window_size.height() - ps.height()) / 2,
                             ps.width(), ps.height());
   params.delegate = lock_view;
   widget->Init(params);
   Shell::GetInstance()->GetContainer(
       ash::internal::kShellWindowId_LockScreenContainer)->
       AddChild(widget->GetNativeView());
   widget->SetContentsView(lock_view);
   widget->Show();
   widget->GetNativeView()->SetName("LockView");
+
+  Shell::GetInstance()->tooltip_controller()->UpdateTooltip(
+      widget->GetNativeView());
 }
 
 }  // namespace shell
 }  // namespace ash