Use mojo volume interfaces for mash and classic ash.

chrome/browser/ui/ash/system_tray_delegate_chromeos.cc

Index: chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
diff --git a/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc b/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
index 5e37efa4dc0b65b2bee58d14286a3560e5d03dbd..77d9c12076246f7febc53007826713be2a0466c1 100644
--- a/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
@@ -28,7 +28,6 @@
 #include "ash/common/system/tray_accessibility.h"
 #include "ash/common/system/update/update_observer.h"
 #include "ash/common/system/user/user_observer.h"
-#include "ash/common/system/volume_control_delegate.h"
 #include "ash/common/wm_shell.h"
 #include "ash/shell.h"
 #include "ash/system/chromeos/rotation/tray_rotation_lock.h"
@@ -73,7 +72,6 @@
 #include "chrome/browser/ui/ash/networking_config_delegate_chromeos.h"
 #include "chrome/browser/ui/ash/system_tray_client.h"
 #include "chrome/browser/ui/ash/system_tray_delegate_utils.h"
-#include "chrome/browser/ui/ash/volume_controller_chromeos.h"
 #include "chrome/browser/ui/ash/vpn_delegate_chromeos.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
@@ -172,7 +170,6 @@ SystemTrayDelegateChromeOS::SystemTrayDelegateChromeOS()
       session_started_(false),
       cast_config_delegate_(nullptr),
       networking_config_delegate_(new NetworkingConfigDelegateChromeos()),
-      volume_control_delegate_(new VolumeController()),
       vpn_delegate_(new VPNDelegateChromeOS),
       weak_ptr_factory_(this) {
   // Register notifications on construction so that events such as
@@ -603,16 +600,6 @@ SystemTrayDelegateChromeOS::GetNetworkingConfigDelegate() const {
   return networking_config_delegate_.get();
 }
 
-ash::VolumeControlDelegate*
-SystemTrayDelegateChromeOS::GetVolumeControlDelegate() const {
-  return volume_control_delegate_.get();
-}
-
-void SystemTrayDelegateChromeOS::SetVolumeControlDelegate(
-    std::unique_ptr<ash::VolumeControlDelegate> delegate) {
-  volume_control_delegate_.swap(delegate);
-}
-
 bool SystemTrayDelegateChromeOS::GetSessionStartTime(
     base::TimeTicks* session_start_time) {
   *session_start_time = session_start_time_;