headless: Add gn settings for embedded build and headless mode

chrome/test/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/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/chrome_tests.gni")
@@ skipping 1086 matching lines @@
         "//ui/resources",
       ]
     } else {
       sources -= [
         "../app/chrome_command_ids.h",
         "../app/chrome_dll_resource.h",
         "../app/chrome_version.rc.version",
         "../browser/media_galleries/fileapi/iapps_finder_impl_win_browsertest.cc",
       ]
     }
-    if (!is_chromeos && use_aura) {
+    if (!is_chromeos && use_aura && use_ash) {
       sources -= [
         # On Windows and Linux, we currently don't support enough of the
         # ash environment to run these unit tests.
         #
         # TODO: enable these on windows and linux.
         "../browser/ui/ash/accelerator_commands_browsertest.cc",
         "../browser/ui/ash/accelerator_controller_browsertest.cc",
         "../browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc",
         "../browser/ui/ash/launcher/launcher_favicon_loader_browsertest.cc",
         "../browser/ui/ash/shelf_browsertest.cc",
@@ skipping 1046 matching lines @@
     "//third_party/mojo/src/mojo/edk/system",
   ]
 
   if (!is_android && use_ash) {
     sources += rebase_path(
             chrome_tests_unit_gypi_values.chrome_test_support_unit_ash_sources,
             ".",
             "//chrome")
   }
 }