Process DisplaySnapshots in PlatformScreen.

services/ui/display/BUILD.gn

 # Copyright 2016 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("//testing/test.gni")
 
 source_set("display") {
   sources = [
     "platform_screen.h",
     "platform_screen_delegate.h",
   ]
 
   deps = [
     "//base",
     "//ui/display",
@@ skipping 10 matching lines @@
       "//skia",
       "//ui/ozone:ozone",
     ]
   } else {
     sources += [
       "platform_screen_impl.cc",
       "platform_screen_impl.h",
     ]
   }
 }
+
+if (use_ozone) {
+  test("display_service_unittests") {
+    sources = [
+      "platform_screen_ozone_unittests.cc",
+    ]
+
+    deps = [
+      ":display",
+      "//base",
+      "//base/test:run_all_unittests",
+      "//base/test:test_support",
+      "//testing/gmock",
+      "//testing/gtest",
+      "//ui/display",
+      "//ui/gfx",
+      "//ui/gfx:test_support",
+      "//ui/ozone",
+    ]
+  }
+}