Revert "chromeos: Fix shelf appearing at login screen under mash"

ash/mus/test/ash_test_impl_mus.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 ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_
 #define ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_
 
 #include "ash/common/test/ash_test_impl.h"
 #include "ash/mus/test/wm_test_base.h"
 #include "base/macros.h"
@@ skipping 24 matching lines @@
   display::Display GetSecondaryDisplay() override;
   bool SetSecondaryDisplayPlacement(
       display::DisplayPlacement::Position position,
       int offset) override;
   void ConfigureWidgetInitParamsForDisplay(
       WmWindow* window,
       views::Widget::InitParams* init_params) override;
   void AddTransientChild(WmWindow* parent, WmWindow* window) override;
 
  private:
-  // Simulates the first user logging in and the session becoming active.
-  // Classic ash handles this via AshTestHelper and TestSessionStateDelegate.
-  void SimulateUserLogin();
-
   // TODO(sky): fold WmTestBase directly into this class when no more subclasses
   // of WmTestBase.
   std::unique_ptr<WmTestBase> wm_test_base_;
 
   DISALLOW_COPY_AND_ASSIGN(AshTestImplMus);
 };
 
 }  // namespace mus
 }  // namespace ash
 
 #endif  // ASH_MUS_TEST_ASH_TEST_IMPL_MUS_H_