Force non-Unicode build in all configurations.

runtime/bin/bin.gypi

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 {
   'variables': {
     'io_cc_file': '<(SHARED_INTERMEDIATE_DIR)/io_gen.cc',
     'json_cc_file': '<(SHARED_INTERMEDIATE_DIR)/json_gen.cc',
     'uri_cc_file': '<(SHARED_INTERMEDIATE_DIR)/uri_gen.cc',
     'utf8_cc_file': '<(SHARED_INTERMEDIATE_DIR)/utf8_gen.cc',
@@ skipping 207 matching lines @@
       'conditions': [
         ['OS=="win"', {
           'sources/' : [
             ['exclude', 'fdutils.h'],
           ],
           # TODO(antonm): fix the implementation.
           # Current implementation accepts char* strings
           # and therefore fails to compile once _UNICODE is
           # enabled.  That should be addressed using -A
           # versions of functions and adding necessary conversions.
-          'msvs_configuration_attributes': {
-            'CharacterSet': '0',
+          'configurations': {
+            'Common_Base': {
+              'msvs_configuration_attributes': {
+                'CharacterSet': '0',
+              },
+            },
           },
         }],
         ['OS=="linux"', {
           'link_settings': {
             'libraries': [
               '-ldl',
             ],
           },
         }],
       ],
@@ skipping 194 matching lines @@
           ],
           'defines': [
             'DART_SHARED_LIB',
           ],
         },
       ],
     }],
   ],
 }