Handle exception when retrieving toJSON function in JSON.stringify.

test/mjsunit/json2.js

Index: test/mjsunit/json2.js
diff --git a/test/mjsunit/json2.js b/test/mjsunit/json2.js
index 0894d779ac14bf3e885a45584327eab018b64448..f048f05290c9bec50418ee37bb821bf5e8c8d3c4 100644
--- a/test/mjsunit/json2.js
+++ b/test/mjsunit/json2.js
@@ -105,6 +105,10 @@ var tojson_via_getter = { get toJSON() {
                           a: 1 };
 TestStringify('321', tojson_via_getter);
 
+assertThrows(function() {
+  JSON.stringify({ get toJSON() { throw "error"; } });
+});
+
 // Test toJSON with key.
 tojson_obj = { toJSON: function(key) { return key + key; } };
 var tojson_with_key_1 = { a: tojson_obj, b: tojson_obj };