More pre-MD cleanup

ash/common/system/tray/system_tray.h

Index: ash/common/system/tray/system_tray.h
diff --git a/ash/common/system/tray/system_tray.h b/ash/common/system/tray/system_tray.h
index 38af857b444b9030eac38370e35cd5dbd4da5bc7..5ded10bd9feea224e5cbc460b4bb939876836c14 100644
--- a/ash/common/system/tray/system_tray.h
+++ b/ash/common/system/tray/system_tray.h
@@ -27,7 +27,6 @@ class SystemTrayItem;
 class TrayAccessibility;
 class TrayAudio;
 class TrayCast;
-class TrayDate;
 class TrayNetwork;
 class TraySystemInfo;
 class TrayTiles;
@@ -145,7 +144,6 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   views::View* GetTrayItemViewForTest(SystemTrayItem* tray_item);
 
   TrayCast* GetTrayCastForTesting() const;
-  TrayDate* GetTrayDateForTesting() const;
   TrayNetwork* GetTrayNetworkForTesting() const;
   TraySystemInfo* GetTraySystemInfoForTesting() const;
   TrayTiles* GetTrayTilesForTesting() const;
@@ -231,7 +229,6 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   TrayAccessibility* tray_accessibility_;
   TrayAudio* tray_audio_;  // May be null.
   TrayCast* tray_cast_;
-  TrayDate* tray_date_;    // null for material design.
   TrayNetwork* tray_network_;
   TrayTiles* tray_tiles_;  // only used in material design.
   TraySystemInfo* tray_system_info_;  // only used in material design.