chromeos: Remove AshTestBase::SupportsMultipleDisplays

ash/test/ash_test_base.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_TEST_ASH_TEST_BASE_H_
 #define ASH_TEST_ASH_TEST_BASE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 120 matching lines @@
     BLOCKED_BY_USER_ADDING_SCREEN,
     NUMBER_OF_BLOCK_REASONS
   };
 
   // Returns the rotation currentl active for the display |id|.
   static display::Display::Rotation GetActiveDisplayRotation(int64_t id);
 
   // Returns the rotation currently active for the internal display.
   static display::Display::Rotation GetCurrentInternalDisplayRotation();
 
-  // Proxy to AshTestHelper::SupportsMultipleDisplays().
-  static bool SupportsMultipleDisplays();
-
   void set_start_session(bool start_session) { start_session_ = start_session; }
 
   // Sets material mode for the test. This will override material mode set via
   // command line switches.
   void set_material_mode(MaterialDesignController::Mode material_mode) {
     CHECK(!setup_called_);
     material_mode_ = material_mode;
   }
 
   AshTestHelper* ash_test_helper() { return ash_test_helper_.get(); }
@@ skipping 46 matching lines @@
   ~NoSessionAshTestBase() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NoSessionAshTestBase);
 };
 
 }  // namespace test
 }  // namespace ash
 
 #endif  // ASH_TEST_ASH_TEST_BASE_H_