Revert "Remove U+180E from whitespace in js_runtime and tests"

tests/corelib_strong/double_parse_test.dart

 // Copyright (c) 2014 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.
 // VMOptions=--no-use-field-guards
 // VMOptions=
 
 import "dart:math" show pow;
 import "package:expect/expect.dart";
 
 const whiteSpace = const [
   "",
   "\x09",
   "\x0a",
   "\x0b",
   "\x0c",
   "\x0d",
   "\x85",    /// 01: ok
   "\xa0",
   "\u1680",
+  "\u180e",
   "\u2000",
   "\u2001",
   "\u2002",
   "\u2003",
   "\u2004",
   "\u2005",
   "\u2006",
   "\u2007",
   "\u2008",
   "\u2009",
@@ skipping 1120 matching lines @@
   testFail("INFINITY");
   testFail("1.#INF");
   testFail("inf");
   testFail("nan");
   testFail("NAN");
   testFail("1.#IND");
   testFail("indef");
   testFail("qnan");
   testFail("snan");
 }