[Isolates] Merge 6700:7030 from bleeding_edge to isolates.

test/mjsunit/regexp.js

Index: test/mjsunit/regexp.js
===================================================================
--- test/mjsunit/regexp.js	(revision 7006)
+++ test/mjsunit/regexp.js	(working copy)
@@ -676,3 +676,17 @@
 assertFalse(re.test("c"));
 assertFalse(re.test(""));
 
+// Valid syntax in ES5.
+re = RegExp("(?:x)*");
+re = RegExp("(x)*");
+
+// Syntax extension relative to ES5, for matching JSC (and ES3).
+// Shouldn't throw.
+re = RegExp("(?=x)*");
+re = RegExp("(?!x)*");
+
+// Should throw. Shouldn't hit asserts in debug mode.
+assertThrows("RegExp('(*)')");
+assertThrows("RegExp('(?:*)')");
+assertThrows("RegExp('(?=*)')");
+assertThrows("RegExp('(?!*)')");