ash: Highlight the items in the uber-tray popup when hovering.

ash/system/user/tray_user.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/user/tray_user.h"
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "base/utf_string_conversions.h"
 #include "grit/ash_strings.h"
@@ skipping 86 matching lines @@
   explicit UserView(ash::user::LoginStatus status)
       : username_(NULL),
         email_(NULL),
         update_(NULL),
         shutdown_(NULL),
         signout_(NULL),
         lock_(NULL) {
     CHECK(status != ash::user::LOGGED_IN_NONE);
     SetLayoutManager(new views::BoxLayout(views::BoxLayout::kVertical,
           0, 0, 0));
+    set_background(views::Background::CreateSolidBackground(SK_ColorWHITE));
 
     if (status != ash::user::LOGGED_IN_GUEST)
       AddUserInfo();
 
     views::View* button_container = new views::View;
     views::BoxLayout *layout = new
         views::BoxLayout(views::BoxLayout::kHorizontal,
             kPaddingAroundButtons,
             kPaddingAroundButtons,
             -1);
@@ skipping 168 matching lines @@
 void TrayUser::DestroyDetailedView() {
 }
 
 void TrayUser::OnUpdateRecommended() {
   if (user_.get())
     user_->RefreshForUpdate();
 }
 
 }  // namespace internal
 }  // namespace ash