headless: Add a Maybe-type

headless/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")
 import("//tools/grit/grit_rule.gni")
 import("//tools/grit/repack.gni")
 
 group("headless") {
   deps = [
@@ skipping 66 matching lines @@
     "lib/headless_content_main_delegate.cc",
     "lib/headless_content_main_delegate.h",
     "lib/renderer/headless_content_renderer_client.cc",
     "lib/renderer/headless_content_renderer_client.h",
     "lib/utility/headless_content_utility_client.cc",
     "lib/utility/headless_content_utility_client.h",
     "public/headless_browser.cc",
     "public/headless_browser.h",
     "public/headless_export.h",
     "public/headless_web_contents.h",
+    "public/util/maybe.h",
   ]
 
   deps = [
     ":pak",
     "//base",
     "//components/devtools_http_handler",
     "//content/public/app:both",
     "//content/public/browser",
     "//content/public/child",
     "//content/public/common",
     "//content/public/renderer",
     "//content/public/utility",
     "//net",
     "//ui/aura",
     "//ui/base",
     "//ui/compositor",
     "//ui/ozone",
     "//url",
   ]
 }
 
 group("headless_tests") {
   testonly = true
 
   deps = [
     ":headless_browsertests",
+    ":headless_unittests",
   ]
 }
 
+test("headless_unittests") {
+  sources = [
+    "public/util/maybe_unittest.cc",
+  ]
+
+  deps = [
+    "//base/test:run_all_unittests",
+    "//base/test:test_support",
+    "//testing/gtest",
+  ]
+}
+
 test("headless_browsertests") {
   sources = [
     "lib/headless_browser_browsertest.cc",
     "lib/headless_web_contents_browsertest.cc",
     "test/headless_browser_test.cc",
     "test/headless_browser_test.h",
     "test/headless_test_launcher.cc",
   ]
 
   defines = [ "HAS_OUT_OF_PROC_TEST_RUNNER" ]
@@ skipping 14 matching lines @@
   sources = [
     "app/headless_shell.cc",
     "app/headless_shell_switches.cc",
     "app/headless_shell_switches.h",
   ]
 
   deps = [
     "//headless:headless_lib",
   ]
 }