Use a valid /prefetch argument when launching a process.

chrome/chrome.gyp

 # 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.
 {
   'variables': {
     'chromium_code': 1,
 
     # Define the common dependencies that contain all the actual
     # Chromium functionality.  This list gets pulled in below by
     # the link of the actual chrome (or chromium) executable on
@@ skipping 727 matching lines @@
             'service/cloud_print/printer_job_queue_handler.h',
             'service/net/service_url_request_context_getter.cc',
             'service/net/service_url_request_context_getter.h',
             'service/service_ipc_server.cc',
             'service/service_ipc_server.h',
             'service/service_main.cc',
             'service/service_process.cc',
             'service/service_process.h',
             'service/service_process_prefs.cc',
             'service/service_process_prefs.h',
-            'service/service_utility_process_host.cc',
-            'service/service_utility_process_host.h',
           ],
           'include_dirs': [
             '..',
           ],
           'conditions': [
             ['use_cups==1', {
               'dependencies': [
                 '../printing/printing.gyp:cups',
               ],
               'sources': [
                 'service/cloud_print/print_system_cups.cc',
               ],
             }],
             ['OS!="win" and use_cups!=1', {
               'sources': [
                 'service/cloud_print/print_system_dummy.cc',
               ],
             }],
-            ['OS!="win"', {
-              'sources!': [
+            ['OS=="win"', {
+              'sources': [
                 'service/service_utility_process_host.cc',
                 'service/service_utility_process_host.h',
               ],
+              'deps': [
+                # TODO(fdoray): Remove this once the PreRead field trial has
+                # expired. crbug.com/577698
+                '../components/components.gyp:startup_metric_utils_common',
+              ],
             }],
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }