Switch 'settings' to 'none', as the former is deprecated.

icu.gyp

 # Copyright (c) 2011 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': {
     'use_system_icu%': 0,
     'icu_use_data_file_flag%': 0,
   },
   'target_defaults': {
@@ skipping 589 matching lines @@
                 '-Wno-tautological-compare',
               ],
             }],
           ],
         },
       ],
     }, { # use_system_icu != 0
       'targets': [
         {
           'target_name': 'system_icu',
-          'type': 'settings',
+          'type': 'none',
           'direct_dependent_settings': {
             'defines': [
               'USE_SYSTEM_ICU',
             ],
           },
           'link_settings': {
             'ldflags': [
               '<!@(icu-config --ldflags)',
             ],
             'libraries': [
@@ skipping 16 matching lines @@
         {
           'target_name': 'icuuc',
           'type': 'none',
           'dependencies': ['system_icu'],
           'export_dependent_settings': ['system_icu'],
         },
       ],
     }],
   ],
 }