Make dates default to the local timezone if none specified

test/test262-es6/test262-es6.status

 # Copyright 2011 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 353 matching lines @@
   'built-ins/Array/symbol-species': [FAIL],
   'built-ins/ArrayBuffer/symbol-species': [FAIL],
   'built-ins/Map/symbol-species': [FAIL],
   'built-ins/Promise/symbol-species': [FAIL],
   'built-ins/RegExp/symbol-species': [FAIL],
   'built-ins/Set/symbol-species': [FAIL],
   'built-ins/Symbol/species/basic': [FAIL],
   'built-ins/Symbol/species/builtin-getter-name': [FAIL],
   'built-ins/Symbol/species/subclassing': [FAIL],
 
-  # https://code.google.com/p/v8/issues/detail?id=4242
-  'built-ins/Date/15.9.1.15-1': [FAIL],
-
   # https://code.google.com/p/v8/issues/detail?id=4004
   'built-ins/Date/prototype/setFullYear/15.9.5.40_1': [FAIL],
 
   # https://code.google.com/p/v8/issues/detail?id=4002
   'built-ins/Error/prototype/S15.11.4_A2': [FAIL],
 
   # https://code.google.com/p/v8/issues/detail?id=4163
   'built-ins/GeneratorPrototype/next/context-constructor-invocation': [FAIL],
 
   # https://code.google.com/p/v8/issues/detail?id=3566
@@ skipping 365 matching lines @@
 
   # BUG(3251225): Tests that timeout with --nocrankshaft.
   'built-ins/decodeURI/S15.1.3.1_A2.4_T1': [SKIP],
   'built-ins/decodeURI/S15.1.3.1_A2.5_T1': [SKIP],
   'built-ins/decodeURIComponent/S15.1.3.2_A2.4_T1': [SKIP],
   'built-ins/decodeURIComponent/S15.1.3.2_A2.5_T1': [SKIP],
   'built-ins/encodeURI/S15.1.3.3_A2.3_T1': [SKIP],
   'built-ins/encodeURIComponent/S15.1.3.4_A2.3_T1': [SKIP],
 }],  # 'arch == arm or arch == mipsel or arch == mips or arch == arm64'
 ]