Rewrite double.parse.

tests/compiler/dart2js/js_parser_test.dart

 // Copyright (c) 2011, 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.
 
 import 'package:expect/expect.dart';
 import 'mock_compiler.dart';
 import '../../../sdk/lib/_internal/compiler/implementation/js/js.dart' as jsAst;
 import '../../../sdk/lib/_internal/compiler/implementation/js/js.dart' show js;
 
 void testExpression(String expression, [String expect = ""]) {
@@ skipping 87 matching lines @@
   // *Can't handle non-empty object literals
   testError('foo({meaning: 42})', 'Expected RBRACE');
   // Literals.
   testExpression('x(false, true, null)');
   // *We should really throw here.
   testExpression('var false = 42');
   testExpression('var new = 42');
   // Bad keyword.
   testError('var typeof = 42', "Expected ALPHA");
   // Malformed decimal/hex.
-  testError('var x = 42.', "Unparseable number");
   testError('var x = 1.1.1', "Unparseable number");
   testError('var x = 0xabcdefga', "Unparseable number");
   testError('var x = 0xabcdef\$a', "Unparseable number");
   testError('var x = 0x ', "Unparseable number");
   // Good hex constants.
   testExpression('var x = 0xff');
   testExpression('var x = 0xff + 0xff');
   testExpression('var x = 0xaF + 0x0123456789abcdefABCDEF');
   // All sorts of keywords are allowed as property names in ES5.
   testExpression('x.new = 0');
@@ skipping 62 matching lines @@
   testExpression("y = a == null ? b : a");
   testExpression("y = a == null ? b + c : a + c");
   testExpression("foo = a ? b : c ? d : e");
   testExpression("foo = a ? b ? c : d : e");
   testExpression("foo = (a = v) ? b = w : c = x ? d = y : e = z");
   testExpression("foo = (a = v) ? b = w ? c = x : d = y : e = z");
   // Stacked assignment.
   testExpression("a = b = c");
   testExpression("var a = b = c");
 }