mash: Migrate tray date view to //ash/common types

ash/system/tray/system_tray_notifier.cc

Index: ash/system/tray/system_tray_notifier.cc
diff --git a/ash/system/tray/system_tray_notifier.cc b/ash/system/tray/system_tray_notifier.cc
index d81c72fe11a1b3da9c55ecb3df12cb0eacb2dfa1..43b3bc48455f82ae71b77f0b473d641af376842c 100644
--- a/ash/system/tray/system_tray_notifier.cc
+++ b/ash/system/tray/system_tray_notifier.cc
@@ -30,14 +30,6 @@ void SystemTrayNotifier::RemoveAudioObserver(AudioObserver* observer) {
   audio_observers_.RemoveObserver(observer);
 }
 
-void SystemTrayNotifier::AddClockObserver(ClockObserver* observer) {
-  clock_observers_.AddObserver(observer);
-}
-
-void SystemTrayNotifier::RemoveClockObserver(ClockObserver* observer) {
-  clock_observers_.RemoveObserver(observer);
-}
-
 void SystemTrayNotifier::AddIMEObserver(IMEObserver* observer) {
   ime_observers_.AddObserver(observer);
 }
@@ -227,28 +219,6 @@ void SystemTrayNotifier::NotifyTracingModeChanged(bool value) {
       OnTracingModeChanged(value));
 }
 
-void SystemTrayNotifier::NotifyRefreshClock() {
-  FOR_EACH_OBSERVER(ClockObserver, clock_observers_, Refresh());
-}
-
-void SystemTrayNotifier::NotifyDateFormatChanged() {
-  FOR_EACH_OBSERVER(ClockObserver,
-                    clock_observers_,
-                    OnDateFormatChanged());
-}
-
-void SystemTrayNotifier::NotifySystemClockTimeUpdated() {
-  FOR_EACH_OBSERVER(ClockObserver,
-                    clock_observers_,
-                    OnSystemClockTimeUpdated());
-}
-
-void SystemTrayNotifier::NotifySystemClockCanSetTimeChanged(bool can_set_time) {
-  FOR_EACH_OBSERVER(ClockObserver,
-                    clock_observers_,
-                    OnSystemClockCanSetTimeChanged(can_set_time));
-}
-
 void SystemTrayNotifier::NotifyRefreshIME() {
   FOR_EACH_OBSERVER(IMEObserver,
                     ime_observers_,