don't mix system and bundled ICU

base/base.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,
   },
   'includes': [
     '../build/win_precompile.gypi',
@@ skipping 858 matching lines @@
     {
       # GN: //base/test:test_support
       'target_name': 'test_support_base',
       'type': 'static_library',
       'dependencies': [
         'base',
         'base_static',
         'base_i18n',
         '../testing/gmock.gyp:gmock',
         '../testing/gtest.gyp:gtest',
+        '../third_party/icu/icu.gyp:icuuc',
         '../third_party/libxml/libxml.gyp:libxml',
         'third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
       ],
       'export_dependent_settings': [
         'base',
       ],
       'conditions': [
         ['os_posix==0', {
           'sources!': [
             'test/scoped_locale.cc',
@@ skipping 669 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }