Re-reland: chromeos: Fix shelf appearing at login screen under mash

chrome/browser/ui/ash/session_controller_client.h

 // Copyright 2016 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 CHROME_BROWSER_UI_ASH_SESSION_CONTROLLER_CLIENT_H_
 #define CHROME_BROWSER_UI_ASH_SESSION_CONTROLLER_CLIENT_H_
 
 #include "ash/public/interfaces/session_controller.mojom.h"
 #include "base/macros.h"
 #include "components/session_manager/core/session_manager_observer.h"
@@ skipping 32 matching lines @@
   void OnSessionStateChanged() override;
 
   // TODO(xiyuan): Remove after SessionStateDelegateChromeOS is gone.
   static bool CanLockScreen();
   static bool ShouldLockScreenAutomatically();
   static ash::AddUserSessionPolicy GetAddUserSessionPolicy();
   static void DoLockScreen();
   static void DoSwitchActiveUser(const AccountId& account_id);
   static void DoCycleActiveUser(bool next_user);
 
+  // Flushes the mojo pipe to ash.
+  static void FlushForTesting();
+
  private:
   // Connects or reconnects to the |session_controller_| interface and set
   // this object as its client.
   void ConnectToSessionControllerAndSetClient();
 
   // Sends session info to ash.
   void SendSessionInfoIfChanged();
 
   // Sends the user session info.
   void SendUserSession(const user_manager::User& user);
 
   // Sends the order of user sessions to ash.
   void SendUserSessionOrder();
 
   // Binds to the client interface.
   mojo::Binding<ash::mojom::SessionControllerClient> binding_;
 
   // SessionController interface in ash.
   ash::mojom::SessionControllerPtr session_controller_;
 
   // Whether the primary user session info is sent to ash.
   bool primary_user_session_sent_ = false;
 
   ash::mojom::SessionInfoPtr last_sent_session_info_;
 
   DISALLOW_COPY_AND_ASSIGN(SessionControllerClient);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_SESSION_CONTROLLER_CLIENT_H_