Added Ash.SystemMenu.DefaultView.VisibleItems histogram.

ash/common/system/chromeos/screen_security/screen_tray_item.cc

 // Copyright 2013 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/screen_security/screen_tray_item.h"
 
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/system/tray/fixed_sized_image_view.h"
 #include "ash/common/system/tray/tray_constants.h"
 #include "ui/base/resource/resource_bundle.h"
@@ skipping 101 matching lines @@
 ScreenNotificationDelegate::~ScreenNotificationDelegate() {}
 
 void ScreenNotificationDelegate::ButtonClick(int button_index) {
   DCHECK_EQ(0, button_index);
   screen_tray_->Stop();
   screen_tray_->RecordStoppedFromNotificationViewMetric();
 }
 
 }  // namespace tray
 
-ScreenTrayItem::ScreenTrayItem(SystemTray* system_tray)
-    : SystemTrayItem(system_tray),
+ScreenTrayItem::ScreenTrayItem(SystemTray* system_tray, UmaType uma_type)
+    : SystemTrayItem(system_tray, uma_type),
       tray_view_(NULL),
       default_view_(NULL),
       is_started_(false),
       stop_callback_(base::Bind(&base::DoNothing)) {}
 
 ScreenTrayItem::~ScreenTrayItem() {}
 
 void ScreenTrayItem::Update() {
   if (tray_view_)
     tray_view_->Update();
@@ skipping 53 matching lines @@
 
   // Center the item dependent on the orientation of the shelf.
   views::BoxLayout::Orientation layout = IsHorizontalAlignment(alignment)
                                              ? views::BoxLayout::kHorizontal
                                              : views::BoxLayout::kVertical;
   tray_view_->SetLayoutManager(new views::BoxLayout(layout, 0, 0, 0));
   tray_view_->Layout();
 }
 
 }  // namespace ash