Refactors std::vector<Display> out of ScreenMus

mash/wm/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("//build/config/ui.gni")
 import("//mojo/public/mojo_application.gni")
 import("//mojo/public/mojo_application_manifest.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//tools/grit/repack.gni")
 
@@ skipping 142 matching lines @@
 }
 
 source_set("unittests") {
   testonly = true
 
   sources = [
     "accelerator_registrar_unittest.cc",
     "app_launch_unittest.cc",
     "frame/move_loop_unittest.cc",
     "layout_manager_unittest.cc",
+    "test/wm_test_screen.cc",
+    "test/wm_test_screen.h",
     "window_manager_unittest.cc",
   ]
 
   deps = [
     ":lib",
     "//base",
     "//base/test:test_config",
     "//components/mus/common:mus_common",
     "//components/mus/public/cpp",
     "//components/mus/public/cpp/tests:unittest_support",
     "//components/mus/public/interfaces",
     "//mash/wm/public/interfaces",
     "//mojo/converters/geometry",
     "//mojo/converters/input_events",
     "//mojo/edk/system",
     "//mojo/gles2",
     "//mojo/platform_handle",
     "//mojo/public/cpp/system",
     "//services/shell/public/cpp:shell_test_support",
     "//testing/gtest",
+    "//ui/aura",
     "//ui/base",
+    "//ui/display",
     "//ui/events",
     "//ui/gfx:test_support",
     "//ui/gfx/geometry",
     "//ui/mojo/geometry:interfaces",
     "//ui/mojo/geometry:util",
+    "//ui/views/mus",
   ]
 
   data_deps = [
     ":wm",
     "//mash/quick_launch",
   ]
 }