mash: Change the MediaDelegate to a Media{Controller,Client}.

ash/common/system/tray/system_tray_notifier.cc

Index: ash/common/system/tray/system_tray_notifier.cc
diff --git a/ash/common/system/tray/system_tray_notifier.cc b/ash/common/system/tray/system_tray_notifier.cc
index e530b8c43a4c3e484b8b9b2ca9d39beb8fd64639..665beda7355c4d81eb9b997f41de588d08073c91 100644
--- a/ash/common/system/tray/system_tray_notifier.cc
+++ b/ash/common/system/tray/system_tray_notifier.cc
@@ -13,7 +13,6 @@
 #if defined(OS_CHROMEOS)
 #include "ash/common/system/chromeos/bluetooth/bluetooth_observer.h"
 #include "ash/common/system/chromeos/enterprise/enterprise_domain_observer.h"
-#include "ash/common/system/chromeos/media_security/media_capture_observer.h"
 #include "ash/common/system/chromeos/network/network_observer.h"
 #include "ash/common/system/chromeos/network/network_portal_detector_observer.h"
 #include "ash/common/system/chromeos/screen_security/screen_capture_observer.h"
@@ -197,21 +196,6 @@ void SystemTrayNotifier::NotifyLogoutDialogDurationChanged(
     observer.OnLogoutDialogDurationChanged(duration);
 }
 
-void SystemTrayNotifier::AddMediaCaptureObserver(
-    MediaCaptureObserver* observer) {
-  media_capture_observers_.AddObserver(observer);
-}
-
-void SystemTrayNotifier::RemoveMediaCaptureObserver(
-    MediaCaptureObserver* observer) {
-  media_capture_observers_.RemoveObserver(observer);
-}
-
-void SystemTrayNotifier::NotifyMediaCaptureChanged() {
-  for (auto& observer : media_capture_observers_)
-    observer.OnMediaCaptureChanged();
-}
-
 void SystemTrayNotifier::AddNetworkObserver(NetworkObserver* observer) {
   network_observers_.AddObserver(observer);
 }