Introduce the ability to wait for the watcher process to initialize.

chrome/chrome_exe.gypi

 # Copyright (c) 2012 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.
 
 {
   'targets': [
     {
       'target_name': 'chrome',
       'type': 'none',
       'dependencies': [ 'chrome_initial', ],
@@ skipping 44 matching lines @@
       'mac_bundle': 1,
       'variables': {
         'use_system_xdg_utils%': 0,
         'enable_wexit_time_destructors': 1,
       },
       'sources': [
         'app/chrome_exe_main_aura.cc',
         'app/chrome_exe_main_mac.cc',
         'app/chrome_exe_main_win.cc',
         'app/chrome_exe_resource.h',
+        'app/chrome_watcher_client_win.cc',
+        'app/chrome_watcher_client_win.h',
         'app/chrome_watcher_command_line_win.cc',
         'app/chrome_watcher_command_line_win.h',
         'app/client_util.cc',
         'app/client_util.h',
         'app/signature_validator_win.cc',
         'app/signature_validator_win.h',
         # Note that due to InitializeSandboxInfo, this must be directly linked
         # into chrome.exe, not into a dependent.
         '<(DEPTH)/content/app/startup_helper_win.cc',
         '<(DEPTH)/content/public/common/content_switches.cc',
@@ skipping 616 matching lines @@
               'dependencies': [
                 'chrome_nacl_win64',
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }