Fix regression in JSON serialization of RegExps.

src/date.js

Index: src/date.js
diff --git a/src/date.js b/src/date.js
index 960147072c27cca7d690fe8beba71d64dffc7ea0..cdc35cbb720a71a4b8ca875bf78b2631fdf402a9 100644
--- a/src/date.js
+++ b/src/date.js
@@ -992,6 +992,13 @@ function DateToISOString() {
 }
 
 
+function CheckJSONPrimitive(val) {
+  if (!IsPrimitive(val))
+    throw MakeTypeError('result_not_primitive', ['toJSON', val]);
+  return val;
+}
+
+
 function DateToJSON(key) {
   return CheckJSONPrimitive(this.toISOString());

[Rico, 2010/12/15 07:46:10]

Two things;
1. If "this" is a custom object, and it has a toISOString method that returns an
object this will throw an error, but it should not. It should only throw an
error if there is no toISOString method.

2. If you agree to the above and change the error message we should delete the
TypeError result_not_primitive since this is the only callsite. Also, we can
delete CheckJSONPrimitive since this is the only place we use it.

[Lasse Reichstein, 2010/12/15 08:59:54]

Rewritten completely, CheckJSONPrimitive removed and result_not_primitive error
message deleted.

 }