Do not show shelf or top chrome hints while in Ash immersive mode

ash/common/material_design/material_design_controller.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_COMMON_MATERIAL_DESIGN_MATERIAL_DESIGN_CONTROLLER_H_
 #define ASH_COMMON_MATERIAL_DESIGN_MATERIAL_DESIGN_CONTROLLER_H_
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 
@@ skipping 25 matching lines @@
   // Returns the currently initialized MaterialDesignController::Mode type for
   // Chrome OS system UI.
   static Mode GetMode();
 
   // Returns true if overview mode is using Material Design.
   static bool IsOverviewMaterial();
 
   // Returns true if Material Design features are enabled for Chrome OS shelf.
   static bool IsShelfMaterial();
 
+  // Returns true if Material Design features are enabled for Chrome OS
+  // immersive mode.
+  static bool IsImmersiveModeMaterial();
+
   // Returns true if Material Design features are enabled for Chrome OS system
   // tray menu.
   static bool IsSystemTrayMenuMaterial();
 
   // Returns true if material design versions of icons should be used in the
   // status tray and system menu.
   static bool UseMaterialDesignSystemIcons();
 
  private:
   friend class test::MaterialDesignControllerTestAPI;
@@ skipping 27 matching lines @@
   // Resets the initialization state to uninitialized. To be used by tests to
   // allow calling Initialize() more than once.
   static void Uninitialize();
 
   DISALLOW_COPY_AND_ASSIGN(MaterialDesignController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_MATERIAL_DESIGN_MATERIAL_DESIGN_CONTROLLER_H_