Use mojo SystemTray interfaces for both mash and classic ash

ash/common/system/tray/system_tray.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/common/system/tray/system_tray.h"
 
 #include "ash/common/key_event_watcher.h"
 #include "ash/common/login_status.h"
 #include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/system/cast/tray_cast.h"
 #include "ash/common/system/date/tray_date.h"
+#include "ash/common/system/tray/system_tray_controller.h"
 #include "ash/common/system/tray/system_tray_delegate.h"
 #include "ash/common/system/tray/system_tray_item.h"
 #include "ash/common/system/tray/tray_bubble_wrapper.h"
 #include "ash/common/system/tray/tray_constants.h"
 #include "ash/common/system/tray_accessibility.h"
 #include "ash/common/system/update/tray_update.h"
 #include "ash/common/system/user/tray_user.h"
 #include "ash/common/system/user/tray_user_separator.h"
 #include "ash/common/system/web_notification/web_notification_tray.h"
 #include "ash/common/wm/container_finder.h"
@@ skipping 634 matching lines @@
     height =
         std::max(0, work_area.height() - bubble_view->GetBoundsInScreen().y());
   }
   if (web_notification_tray_)
     web_notification_tray_->SetTrayBubbleHeight(height);
 }
 
 base::string16 SystemTray::GetAccessibleTimeString(
     const base::Time& now) const {
   base::HourClockType hour_type =
-      WmShell::Get()->system_tray_delegate()->GetHourClockType();
+      WmShell::Get()->system_tray_controller()->hour_clock_type();
   return base::TimeFormatTimeOfDayWithHourClockType(now, hour_type,
                                                     base::kKeepAmPm);
 }
 
 void SystemTray::SetShelfAlignment(ShelfAlignment alignment) {
   if (alignment == shelf_alignment())
     return;
   TrayBackgroundView::SetShelfAlignment(alignment);
   UpdateAfterShelfAlignmentChange(alignment);
   // Destroy any existing bubble so that it is rebuilt correctly.
@@ skipping 196 matching lines @@
           .work_area()
           .height();
   if (work_area_height > 0) {
     UMA_HISTOGRAM_CUSTOM_COUNTS(
         "Ash.SystemMenu.PercentageOfWorkAreaHeightCoveredByMenu",
         100 * bubble_view->height() / work_area_height, 1, 300, 100);
   }
 }
 
 }  // namespace ash