Add the supporting code for the cast system tray integration

ash/system/tray/system_tray_notifier.h

 // 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.
 
 #ifndef ASH_SYSTEM_TRAY_SYSTEM_TRAY_NOTIFIER_H_
 #define ASH_SYSTEM_TRAY_SYSTEM_TRAY_NOTIFIER_H_
 
 #include <string>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "ash/system/audio/audio_observer.h"
 #include "ash/system/bluetooth/bluetooth_observer.h"
+#include "ash/system/cast/cast_observer.h"
 #include "ash/system/chromeos/tray_tracing.h"
 #include "ash/system/date/clock_observer.h"
 #include "ash/system/ime/ime_observer.h"
 #include "ash/system/locale/locale_observer.h"
 #include "ash/system/tray_accessibility.h"
 #include "ash/system/user/update_observer.h"
 #include "ash/system/user/user_observer.h"
 #include "base/observer_list.h"
 
 #if defined(OS_CHROMEOS)
@@ skipping 25 matching lines @@
 
   void AddAccessibilityObserver(AccessibilityObserver* observer);
   void RemoveAccessibilityObserver(AccessibilityObserver* observer);
 
   void AddAudioObserver(AudioObserver* observer);
   void RemoveAudioObserver(AudioObserver* observer);
 
   void AddBluetoothObserver(BluetoothObserver* observer);
   void RemoveBluetoothObserver(BluetoothObserver* observer);
 
+  void AddCastObserver(CastObserver* observer);
+  void RemoveCastObserver(CastObserver* observer);
+
   void AddClockObserver(ClockObserver* observer);
   void RemoveClockObserver(ClockObserver* observer);
 
   void AddIMEObserver(IMEObserver* observer);
   void RemoveIMEObserver(IMEObserver* observer);
 
   void AddLocaleObserver(LocaleObserver* observer);
   void RemoveLocaleObserver(LocaleObserver* observer);
 
   void AddTracingObserver(TracingObserver* observer);
@@ skipping 77 matching lines @@
                               const base::string16& helper_name);
   void NotifyScreenShareStop();
   void NotifyLastWindowClosed();
   void NotifyVirtualKeyboardSuppressionChanged(bool suppressed);
 #endif
 
  private:
   ObserverList<AccessibilityObserver> accessibility_observers_;
   ObserverList<AudioObserver> audio_observers_;
   ObserverList<BluetoothObserver> bluetooth_observers_;
+  ObserverList<CastObserver> cast_observers_;
   ObserverList<ClockObserver> clock_observers_;
   ObserverList<IMEObserver> ime_observers_;
   ObserverList<LocaleObserver> locale_observers_;
   ObserverList<TracingObserver> tracing_observers_;
   ObserverList<UpdateObserver> update_observers_;
   ObserverList<UserObserver> user_observers_;
 #if defined(OS_CHROMEOS)
   ObserverList<LogoutButtonObserver> logout_button_observers_;
   ObserverList<SessionLengthLimitObserver> session_length_limit_observers_;
   ObserverList<NetworkObserver> network_observers_;
   ObserverList<NetworkPortalDetectorObserver>
       network_portal_detector_observers_;
   ObserverList<EnterpriseDomainObserver> enterprise_domain_observers_;
   ObserverList<MediaCaptureObserver> media_capture_observers_;
   ObserverList<ScreenCaptureObserver> screen_capture_observers_;
   ObserverList<ScreenShareObserver> screen_share_observers_;
   ObserverList<LastWindowClosedObserver> last_window_closed_observers_;
   ObserverList<VirtualKeyboardObserver> virtual_keyboard_observers_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(SystemTrayNotifier);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_TRAY_SYSTEM_TRAY_NOTIFIER_H_