MD system tray: Add user metrics for clicks on the Bluetooth toggle switch.

ash/common/system/chromeos/bluetooth/tray_bluetooth.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/chromeos/bluetooth/tray_bluetooth.h"
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/system/tray/hover_highlight_view.h"
 #include "ash/common/system/tray/system_tray.h"
 #include "ash/common/system/tray/system_tray_delegate.h"
@@ skipping 432 matching lines @@
     const std::string device_id = find->second;
     if (FoundDevice(device_id, connecting_devices_, nullptr, nullptr))
       return;
 
     UpdateClickedDevice(device_id, view);
     delegate->ConnectToBluetoothDevice(device_id);
   }
 
   void HandleButtonPressed(views::Button* sender,
                            const ui::Event& event) override {
-    if (sender == toggle_)
-      WmShell::Get()->system_tray_delegate()->ToggleBluetooth();
-    else if (sender == settings_)
+    if (sender == toggle_) {
+      SystemTrayDelegate* delegate = WmShell::Get()->system_tray_delegate();
+      WmShell::Get()->RecordUserMetricsAction(
+          delegate->GetBluetoothEnabled() ? UMA_STATUS_AREA_BLUETOOTH_DISABLED
+                                          : UMA_STATUS_AREA_BLUETOOTH_ENABLED);
+      delegate->ToggleBluetooth();
+    } else if (sender == settings_) {
       ShowSettings();
-    else
+    } else {
       NOTREACHED();
+    }
   }
 
   void CreateExtraTitleRowButtons() override {
     if (login_ == LoginStatus::LOCKED)
       return;
 
     DCHECK(!toggle_);
     DCHECK(!settings_);
 
     tri_view()->SetContainerVisible(TriView::Container::END, true);
@@ skipping 150 matching lines @@
     detailed_->Update();
 }
 
 void TrayBluetooth::OnBluetoothDiscoveringChanged() {
   if (!detailed_)
     return;
   detailed_->Update();
 }
 
 }  // namespace ash