Fixed a few more incompatibilities

src/regexp-delay.js

Index: src/regexp-delay.js
diff --git a/src/regexp-delay.js b/src/regexp-delay.js
index 66f23b00f182ebf60767d70b1b9068c38162954e..39fae34200739fce8515b2c5fda249a061e6f13d 100644
--- a/src/regexp-delay.js
+++ b/src/regexp-delay.js
@@ -160,6 +160,9 @@ function DoRegExpExecGlobal(regexp, string) {
 
 
 function RegExpExec(string) {
+  if (!IS_REGEXP(this)) {
+    throw MakeTypeError('method_called_on_incompatible', ['RegExp.prototype.exec', this]);
+  }
   if (%_ArgumentsLength() == 0) {
     if (IS_UNDEFINED(regExpInput)) {
       throw MakeError('no_input_to_regexp', [this]);