GN: Get os="chromeos" use_ozone=true to compile

ui/display/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/ui.gni")
 
 component("display") {
   sources = [
     "chromeos/display_configurator.cc",
     "chromeos/display_configurator.h",
@@ skipping 100 matching lines @@
     "//ui/display/util",
     "//ui/gfx/geometry",
   ]
 
   if (is_chromeos) {
     deps += [
       ":display",
       "//ui/display/types",
     ]
   }
+
+  if (use_ozone) {
+    sources -= [
+      "chromeos/x11/display_util_x11_unittest.cc",
+      "chromeos/x11/native_display_event_dispatcher_x11_unittest.cc",
+    ]
+  }
+      
 }