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

tests/lib_strong/math/math_parse_double_test.dart

 // 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.
 
 // We temporarily test both the new math library and the old Math
 // class. This can easily be simplified once we get rid of the Math
 // class entirely.
 library math_parse_double_test;
 import "package:expect/expect.dart";
 
 void parseDoubleThrowsFormatException(str) {
   Expect.throws(() => double.parse(str), (e) => e is FormatException);
 }
 
 void runTest(double expected, String input) {
   Expect.equals(expected, double.parse(input));
   Expect.equals(expected, double.parse(" $input "));
   Expect.equals(expected, double.parse(" $input"));
   Expect.equals(expected, double.parse("$input "));
   Expect.equals(expected, double.parse("+$input"));
   Expect.equals(expected, double.parse(" +$input "));
   Expect.equals(expected, double.parse("+$input "));
   Expect.equals(expected, double.parse("\xA0 $input\xA0 "));
   Expect.equals(expected, double.parse(" \xA0$input"));
   Expect.equals(expected, double.parse("$input \xA0"));
   Expect.equals(expected, double.parse("\xA0 +$input\xA0 "));
   Expect.equals(expected, double.parse("+$input\xA0 "));
   Expect.equals(expected, double.parse("\u205F $input\u205F "));
+  Expect.equals(expected, double.parse(" \u180E$input"));
   Expect.equals(expected, double.parse("$input \u2006"));
   Expect.equals(expected, double.parse("\u1680 +$input\u1680 "));
   Expect.equals(-expected, double.parse("-$input"));
   Expect.equals(-expected, double.parse(" -$input "));
   Expect.equals(-expected, double.parse("-$input "));
   Expect.equals(-expected, double.parse("\xA0 -$input\xA0 "));
   Expect.equals(-expected, double.parse("-$input\xA0 "));
   Expect.equals(-expected, double.parse("\u1680 -$input\u1680 "));
 }
 
@@ skipping 120 matching lines @@
   parseDoubleThrowsFormatException("-0x00000ABCDEF");
   parseDoubleThrowsFormatException("   0x00000abcdef   ");
   parseDoubleThrowsFormatException("   0x00000ABCDEF   ");
   parseDoubleThrowsFormatException("   -0x00000abcdef   ");
   parseDoubleThrowsFormatException("   -0x00000ABCDEF   ");
   parseDoubleThrowsFormatException("   -INFINITY   ");
   parseDoubleThrowsFormatException("   NAN   ");
   parseDoubleThrowsFormatException("   inf   ");
   parseDoubleThrowsFormatException("   nan   ");
 }