Make a test not depend on system settings.

ui/base/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/compiler/compiler.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 
 if (is_android) {
@@ skipping 581 matching lines @@
   ]
 
   if (!is_ios) {
     sources += [
       "test/nswindow_fullscreen_notification_waiter.h",
       "test/nswindow_fullscreen_notification_waiter.mm",
       "test/scoped_fake_nswindow_focus.h",
       "test/scoped_fake_nswindow_focus.mm",
       "test/scoped_fake_nswindow_fullscreen.h",
       "test/scoped_fake_nswindow_fullscreen.mm",
+      "test/scoped_preferred_scroller_style_legacy_mac.h",
+      "test/scoped_preferred_scroller_style_legacy_mac.mm",
       "test/test_clipboard.cc",
       "test/test_clipboard.h",
       "test/windowed_nsnotification_observer.h",
       "test/windowed_nsnotification_observer.mm",
     ]
   } else {
     sources += [
       "test/ios/keyboard_appearance_listener.h",
       "test/ios/keyboard_appearance_listener.mm",
       "test/ios/ui_view_test_utils.h",
@@ skipping 280 matching lines @@
   }
   if (is_mac) {
     data += [ "$root_out_dir/ui_unittests Framework.framework/" ]
 
     if (is_asan && symbol_level == 0) {
       data += [ "$root_out_dir/ui_base_unittests.dSYM/" ]
     }
   }
 }
 # TODO(GYP) Mac (ui_base_tests_bundle)