[regexp] Port RegExp getters and setters

test/mjsunit/messages.js

Index: test/mjsunit/messages.js
diff --git a/test/mjsunit/messages.js b/test/mjsunit/messages.js
index 30abc197e9b941bc80a038633409af23a1996dcb..33ed2b0daca2846b437c905c87977838c4d2a53d 100644
--- a/test/mjsunit/messages.js
+++ b/test/mjsunit/messages.js
@@ -123,11 +123,6 @@ test(function() {
 }, "First argument to String.prototype.startsWith " +
    "must not be a regular expression", TypeError);
 
-// kFlagsGetterNonObject
-test(function() {
-  Object.getOwnPropertyDescriptor(RegExp.prototype, "flags").get.call(1);
-}, "RegExp.prototype.flags getter called on non-object 1", TypeError);
-
 // kFunctionBind
 test(function() {
   Function.prototype.bind.call(1);