Turn on want_separate_host_toolset on by default, as it's on by default in chrome

icu.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': {
     'use_system_icu%': 0,
     'icu_use_data_file_flag%': 0,
-    'want_separate_host_toolset%': 0,
+    'want_separate_host_toolset%': 1,
   },
   'target_defaults': {
     'direct_dependent_settings': {
       'defines': [
         # Tell ICU to not insert |using namespace icu;| into its headers,
         # so that chrome's source explicitly has to use |icu::|.
         'U_USING_ICU_NAMESPACE=0',
       ],
     },
     'defines': [
@@ skipping 835 matching lines @@
               'toolsets': ['target'],
             }, {
               'toolsets': ['host', 'target'],
             }],
           ],
         },
       ],
     }],
   ],
 }