Adding mac support for Remoting host GN builds.

remoting/remoting_version.gni

 # 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/chrome_build.gni")
 
 _version_py_abspath = "//build/util/version.py"
 _remoting_version_abspath = "//remoting/VERSION"
 if (is_chrome_branded) {
   _remoting_branding_abspath = "//remoting/branding_Chrome"
 } else {
   _remoting_branding_abspath = "//remoting/branding_Chromium"
 }
 
 # Set these files as being input dependencies to the scripts, so the build will
 # be re-run if the files change.
 remoting_version_files = [
   _remoting_version_abspath,
   _remoting_branding_abspath,
 ]
 
 _remoting_version_path = rebase_path(_remoting_version_abspath, root_build_dir)
 _remoting_branding_path =
     rebase_path(_remoting_branding_abspath, root_build_dir)
 
-prefpane_bundle_name = exec_script(_version_py_abspath,
-                                   [
-                                     "-f",
-                                     _remoting_branding_path,
-                                     "-t \"@MAC_PREFPANE_BUNDLE_NAME@\"",
-                                   ],
-                                   "string",
-                                   remoting_version_files)
+_branding_dictionary_template = "mac_host_bundle = \"@MAC_HOST_BUNDLE_NAME@\" " + "mac_native_messaging_bundle = \"@MAC_NATIVE_MESSAGING_HOST_BUNDLE_NAME@\" " + "mac_remote_assistance_bundle = \"@MAC_REMOTE_ASSISTANCE_HOST_BUNDLE_NAME@\" " + "prefpane_bundle_name = \"@MAC_PREFPANE_BUNDLE_NAME@\" " + "host_bundle_name = \"@MAC_HOST_BUNDLE_NAME@\" "
 
-host_bundle_name = exec_script(_version_py_abspath,
-                               [
-                                 "-f",
-                                 _remoting_branding_path,
-                                 "-t \"@MAC_HOST_BUNDLE_NAME@\"",
-                               ],
-                               "string",
-                               remoting_version_files)
+_result = exec_script(_version_py_abspath,
+                      [
+                        "-f",
+                        _remoting_branding_path,
+                        "-t",
+                        _branding_dictionary_template,
+                      ],
+                      "scope",
+                      remoting_version_files)
+
+prefpane_bundle_name = _result.prefpane_bundle_name
+host_bundle_name = _result.host_bundle_name
+me2me_host_bundle_name = _result.mac_host_bundle
+native_messaging_host_bundle_name = _result.mac_native_messaging_bundle
+remote_assistance_host_bundle_name = _result.mac_remote_assistance_bundle