Added Ash.SystemMenu.DefaultView.VisibleItems histogram.

ash/common/system/cast/tray_cast.cc

 // Copyright 2015 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/cast/tray_cast.h"
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/shelf_types.h"
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/system/chromeos/screen_security/screen_tray_item.h"
@@ skipping 514 matching lines @@
     if (it != receiver_activity_map_.end()) {
       cast_config_delegate->CastToReceiver(it->second);
       WmShell::Get()->RecordUserMetricsAction(
           UMA_STATUS_AREA_DETAILED_CAST_VIEW_LAUNCH_CAST);
     }
   }
 }
 
 }  // namespace tray
 
-TrayCast::TrayCast(SystemTray* system_tray) : SystemTrayItem(system_tray) {
+TrayCast::TrayCast(SystemTray* system_tray)
+    : SystemTrayItem(system_tray, UMA_CAST) {
   WmShell::Get()->AddShellObserver(this);
 }
 
 TrayCast::~TrayCast() {
   WmShell::Get()->RemoveShellObserver(this);
   if (added_observer_)
     GetCastConfigDelegate()->RemoveObserver(this);
 }
 
 void TrayCast::StartCastForTest(const std::string& receiver_id) {
@@ skipping 115 matching lines @@
   is_casting_ = started;
   UpdatePrimaryView();
 }
 
 void TrayCast::UpdateAfterShelfAlignmentChange(ShelfAlignment alignment) {
   if (tray_)
     tray_->UpdateAlignment(alignment);
 }
 
 }  // namespace ash