Reapply "Port regexp tests from V8 to Dart."

tests/corelib/regexp/regress-6-9-regexp_test.dart

Index: tests/corelib/regexp/regress-6-9-regexp_test.dart
diff --git a/runtime/third_party/double-conversion/src/strtod.h b/tests/corelib/regexp/regress-6-9-regexp_test.dart
similarity index 69%
copy from runtime/third_party/double-conversion/src/strtod.h
copy to tests/corelib/regexp/regress-6-9-regexp_test.dart
index ed0293b8f54a373762f17fe4dd70f2896eb1d193..3fbef8701375834dd4d660f5549167dc91b0a870 100644
--- a/runtime/third_party/double-conversion/src/strtod.h
+++ b/tests/corelib/regexp/regress-6-9-regexp_test.dart
@@ -1,4 +1,5 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright (c) 2014, the Dart project authors. All rights reserved.
+// Copyright 2009 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:
@@ -25,21 +26,11 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifndef DOUBLE_CONVERSION_STRTOD_H_
-#define DOUBLE_CONVERSION_STRTOD_H_
+import 'v8_regexp_utils.dart';
+import 'package:expect/expect.dart';
 
-#include "utils.h"
+void main() {
+  // Check that the perfect mask check isn't overly optimistic.
 
-namespace double_conversion {
-
-// The buffer must only contain digits in the range [0-9]. It must not
-// contain a dot or a sign. It must not start with '0', and must not be empty.
-double Strtod(Vector<const char> buffer, int exponent);
-
-// The buffer must only contain digits in the range [0-9]. It must not
-// contain a dot or a sign. It must not start with '0', and must not be empty.
-float Strtof(Vector<const char> buffer, int exponent);
-
-}  // namespace double_conversion
-
-#endif  // DOUBLE_CONVERSION_STRTOD_H_
+  assertFalse(new RegExp(r"[6-9]").hasMatch('2'));
+}