Revert of ash: Use system tray mojo interface to show system update tray icon

ash/common/system/tray/system_tray_delegate.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_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_DELEGATE_H_
 #define ASH_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_DELEGATE_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 33 matching lines @@
   std::string address;
   base::string16 display_name;
   bool connected;
   bool connecting;
   bool paired;
   device::BluetoothDeviceType device_type;
 };
 
 using BluetoothDeviceList = std::vector<BluetoothDeviceInfo>;
 
+struct ASH_EXPORT UpdateInfo {
+  enum UpdateSeverity {
+    UPDATE_NONE,
+    UPDATE_LOW,
+    UPDATE_ELEVATED,
+    UPDATE_HIGH,
+    UPDATE_SEVERE,
+    UPDATE_CRITICAL,
+  };
+
+  UpdateInfo();
+  ~UpdateInfo();
+
+  UpdateSeverity severity;
+  bool update_required;
+  bool factory_reset_required;
+};
+
 class NetworkingConfigDelegate;
 
 // SystemTrayDelegate is intended for delegating tasks in the System Tray to the
 // application (e.g. Chrome). These tasks should be limited to application
 // (browser) specific tasks. For non application specific tasks, where possible,
 // components/, chromeos/, device/, etc., code should be used directly. If more
 // than one related method is being added, consider adding an additional
 // specific delegate (e.g. CastConfigDelegate).
 //
 // These methods should all have trivial default implementations for platforms
@@ skipping 34 matching lines @@
 
   // Returns true if the current user is supervised: has legacy supervised
   // account or kid account.
   virtual bool IsUserSupervised() const;
 
   // Returns true if the current user is child.
   // TODO(merkulova): remove on FakeUserManager componentization.
   // crbug.com/443119
   virtual bool IsUserChild() const;
 
+  // Fills |info| structure (which must not be null) with current update info.
+  virtual void GetSystemUpdateInfo(UpdateInfo* info) const;
+
   // Returns true if settings menu item should appear.
   virtual bool ShouldShowSettings() const;
 
   // Returns true if notification tray should appear.
   virtual bool ShouldShowNotificationTray() const;
 
   // Shows information about enterprise enrolled devices.
   virtual void ShowEnterpriseInfo();
 
   // Shows login UI to add other users to this session.
@@ skipping 76 matching lines @@
   // Creates a system tray item for display rotation lock.
   // TODO(jamescook): Remove this when mus has support for display management
   // and we have a DisplayManager equivalent. See http://crbug.com/548429
   virtual std::unique_ptr<SystemTrayItem> CreateRotationLockTrayItem(
       SystemTray* tray);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_SYSTEM_TRAY_DELEGATE_H_