UMA: How often are different network error screens encountered during OOBE

chrome/chrome_browser_chromeos.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.
 
 {
   'variables': {
     # These files lists are shared with the GN build.
     'browser_chromeos_sources': [
         # All .cc, .h, .m, and .mm files under browser/chromeos, except for tests
@@ skipping 437 matching lines @@
         'browser/chromeos/login/easy_unlock/easy_unlock_types.cc',
         'browser/chromeos/login/easy_unlock/easy_unlock_types.h',
         'browser/chromeos/login/enrollment/auto_enrollment_check_screen.cc',
         'browser/chromeos/login/enrollment/auto_enrollment_check_screen.h',
         'browser/chromeos/login/enrollment/auto_enrollment_check_screen_actor.h',
         'browser/chromeos/login/enrollment/auto_enrollment_controller.cc',
         'browser/chromeos/login/enrollment/auto_enrollment_controller.h',
         'browser/chromeos/login/enrollment/enrollment_screen.cc',
         'browser/chromeos/login/enrollment/enrollment_screen.h',
         'browser/chromeos/login/enrollment/enrollment_screen_actor.h',
+        'browser/chromeos/login/error_screens_histogram_helper.cc',
+        'browser/chromeos/login/error_screens_histogram_helper.h',
         'browser/chromeos/login/existing_user_controller.cc',
         'browser/chromeos/login/existing_user_controller.h',
         'browser/chromeos/login/help_app_launcher.cc',
         'browser/chromeos/login/help_app_launcher.h',
         'browser/chromeos/login/helper.cc',
         'browser/chromeos/login/helper.h',
         'browser/chromeos/login/hwid_checker.cc',
         'browser/chromeos/login/hwid_checker.h',
         'browser/chromeos/login/language_list.cc',
         'browser/chromeos/login/language_list.h',
@@ skipping 779 matching lines @@
         'browser/chromeos/attestation/attestation_signed_data.proto',
       ],
       'variables': {
         'proto_in_dir': 'browser/chromeos/attestation',
         'proto_out_dir': 'chrome/browser/chromeos/attestation',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }