Convert startup_metric_utils to use mojo.

chrome/chrome_common.gypi

 # Copyright (c) 2013 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': {
     # File lists shared with GN build.
     'chrome_common_sources': [
       'common/all_messages.h',
       'common/attrition_experiments.h',
@@ skipping 327 matching lines @@
         '<(DEPTH)/components/components.gyp:favicon_base',
         '<(DEPTH)/components/components.gyp:flags_ui_switches',
         '<(DEPTH)/components/components.gyp:gcm_driver_common',
         '<(DEPTH)/components/components.gyp:json_schema',
         '<(DEPTH)/components/components.gyp:metrics',
         '<(DEPTH)/components/components.gyp:metrics_net',
         '<(DEPTH)/components/components.gyp:network_session_configurator_switches',
         '<(DEPTH)/components/components.gyp:omnibox_common',
         '<(DEPTH)/components/components.gyp:policy',
         '<(DEPTH)/components/components.gyp:policy_component_common',
-        # TODO(fdoray): Remove this once the PreRead field trial has expired.
-        # crbug.com/577698
-        '<(DEPTH)/components/components.gyp:startup_metric_utils_common',
         '<(DEPTH)/components/components.gyp:translate_core_common',
         '<(DEPTH)/components/components.gyp:variations',
         '<(DEPTH)/components/components.gyp:version_info',
         '<(DEPTH)/components/components_strings.gyp:components_strings',
         '<(DEPTH)/components/prefs/prefs.gyp:prefs',
         '<(DEPTH)/components/url_formatter/url_formatter.gyp:url_formatter',
         '<(DEPTH)/content/content.gyp:content_common',
         '<(DEPTH)/crypto/crypto.gyp:crypto',
         '<(DEPTH)/net/net.gyp:net',
         '<(DEPTH)/skia/skia.gyp:skia',
@@ skipping 146 matching lines @@
           'dependencies': [
             '<(DEPTH)/url/ipc/url_ipc.gyp:url_ipc',
         ],
         }],
         ['OS=="win"', {
           'include_dirs': [
             '<(DEPTH)/third_party/wtl/include',
           ],
           'dependencies': [
             '<(DEPTH)/components/components.gyp:dom_distiller_core',  # Needed by chrome_content_client.cc.
+            # TODO(fdoray): Remove this once the PreRead field trial has
+            # expired. crbug.com/577698
+            '<(DEPTH)/components/components.gyp:startup_metric_utils_common',

[erikchen, 2016/06/07 16:01:37]

why do we need this on win, but not other OSes?

[Sam McNally, 2016/06/08 00:31:44]

startup_metric_utils_common used to contain the messages files, but now only
contains pre_read_field_trial_utils_win.* so is empty on platforms other than
Windows. Empty static_library targets don't work on Mac because libtool gets
upset. The workaround was to only use startup_metric_utils_common on Windows.

           ],
           'all_dependent_settings': {
             'msvs_settings': {
               'VCLinkerTool': {
                 'AdditionalDependencies': [
                   'wintrust.lib',
                 ],
               },
             },
           },
@@ skipping 169 matching lines @@
           ],
           'dependencies': [
             'installer_util',
             '../base/base.gyp:base',
           ],
         },
       ],
     }],
   ],
 }