[Chrome OS MD] Draw a 1px separator between 2 tray items

ash/common/system/chromeos/session/logout_button_tray.cc

 // Copyright 2014 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/common/system/chromeos/session/logout_button_tray.h"
 
 #include <memory>
 #include <utility>
 
 #include "ash/common/shelf/shelf_types.h"
@@ skipping 82 matching lines @@
 
 LogoutButton::~LogoutButton() {}
 
 LogoutButtonTray::LogoutButtonTray(WmShelf* wm_shelf)
     : TrayBackgroundView(wm_shelf),
       button_(NULL),
       login_status_(LoginStatus::NOT_LOGGED_IN),
       show_logout_button_in_tray_(false) {
   button_ = new LogoutButton(this);
   tray_container()->AddChildView(button_);
-  tray_container()->SetBorder(views::Border::NullBorder());
   WmShell::Get()->system_tray_notifier()->AddLogoutButtonObserver(this);
 }
 
 LogoutButtonTray::~LogoutButtonTray() {
   WmShell::Get()->system_tray_notifier()->RemoveLogoutButtonObserver(this);
 }
 
 void LogoutButtonTray::SetShelfAlignment(ShelfAlignment alignment) {
   TrayBackgroundView::SetShelfAlignment(alignment);
-  tray_container()->SetBorder(views::Border::NullBorder());
 }
 
 base::string16 LogoutButtonTray::GetAccessibleNameForTray() {
   return button_->GetText();
 }
 
 void LogoutButtonTray::HideBubbleWithView(
     const views::TrayBubbleView* bubble_view) {}
 
 void LogoutButtonTray::ClickedOutsideBubble() {}
@@ skipping 28 matching lines @@
   UpdateVisibility();
 }
 
 void LogoutButtonTray::UpdateVisibility() {
   SetVisible(show_logout_button_in_tray_ &&
              login_status_ != LoginStatus::NOT_LOGGED_IN &&
              login_status_ != LoginStatus::LOCKED);
 }
 
 }  // namespace ash