Make unit_tests compile in Mac GN

chrome/browser/apps/app_shim/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.
+
+# This is the part of the Chrome browser process responsible for launching and
+# communicating with app_shim processes on Mac.
+#
+# GYP version: chrome/browser/apps/app_shim/browser_app_shim.gypi:browser_app_shim
+source_set("app_shim") {
+  sources = [
+    "app_shim_handler_mac.cc",
+    "app_shim_handler_mac.h",
+    "app_shim_host_mac.cc",
+    "app_shim_host_mac.h",
+    "app_shim_host_manager_mac.h",
+    "app_shim_host_manager_mac.mm",
+    "extension_app_shim_handler_mac.cc",
+    "extension_app_shim_handler_mac.h",
+    "unix_domain_socket_acceptor.cc",
+    "unix_domain_socket_acceptor.h",
+  ]
+
+  deps = [
+    "//content/public/browser",
+    "//content/public/common",
+  ]
+}