GlobalFuncProtoSetterFunctor sometimes fails to get caller frame. It skips the first frame, then there is no more frame so m_allowsAccess does not get initialized. Happens during: JSTests/stress/proxy-json-path.js Found after landing patch for Bug 161455 because it started throwing a TypeError when trying to set __proto__ instead of merely ignoring the call.
Sending back to Chris since he'll be looking into this.
Dropped this code in Bug 161455. *** This bug has been marked as a duplicate of bug 161455 ***