Consolidate two IsArcWindow functions to reduce code duplication

components/arc/BUILD.gn

 # Copyright 2015 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("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 
 static_library("arc") {
   sources = [
     "arc_service_manager.cc",
@@ skipping 98 matching lines @@
     "arc_session_runner.cc",
     "arc_session_runner.h",
     "arc_stop_reason.cc",
     "arc_stop_reason.h",
     "arc_util.cc",
     "arc_util.h",
     "instance_holder.h",
   ]
 
   deps = [
+    "//ash:ash",
+    "//ash/shared:app_types",
     "//base",
     "//chromeos",
     "//components/user_manager",
     "//mojo/edk/system",
   ]
 
   public_deps = [
     ":arc_bindings",
   ]
 }
@@ skipping 89 matching lines @@
     "intent_helper/font_size_util_unittest.cc",
     "intent_helper/intent_filter_unittest.cc",
     "intent_helper/link_handler_model_impl_unittest.cc",
     "intent_helper/local_activity_resolver_unittest.cc",
     "intent_helper/page_transition_util_unittest.cc",
     "kiosk/arc_kiosk_bridge_unittest.cc",
   ]
 
   deps = [
     ":arc_test_support",
+    "//ash:ash",
+    "//ash/shared:app_types",
     "//base",
     "//base/test:test_support",
     "//chromeos",
     "//device/bluetooth",
     "//mojo/public/cpp/system:system",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/aura",
     "//ui/aura:test_support",
     "//ui/base:test_support",
     "//ui/base/ime",
     "//ui/events",
     "//ui/events:dom_keycode_converter",
     "//url:url",
   ]
 }