Revert of Add all components to "gn check".

components/exo/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("//testing/test.gni")
 
 source_set("exo") {
   sources = [
     "buffer.cc",
     "buffer.h",
@@ skipping 67 matching lines @@
     "//base",
     "//cc",
     "//components/user_manager",
     "//gpu/command_buffer/client:gles2_interface",
     "//skia",
     "//testing/gtest",
     "//ui/aura",
     "//ui/gfx",
     "//ui/keyboard",
     "//ui/message_center",
-    "//ui/ozone",
     "//ui/views",
   ]
 }
 
 test("exo_unittests") {
   sources = [
     "test/run_all_unittests.cc",
   ]
   deps = [
     ":unit_tests",
     "//ash:test_support",
     "//base",
     "//base/test:test_support",
   ]
   if (is_linux) {
     deps += [ "//components/exo/wayland:unit_tests" ]
   }
 }