byteArray: Do not use JSCLASS_NEW_RESOLVE_GETS_START

It is a flag that has been removed in recent versions of libmozjs,
and is not something that we should depend on. This is a simple case
that tries to emulate the behavior of JSCLASS_NEW_RESOLVE_GETS_START;
a future code cleanup will simplify code here more.

https://bugzilla.gnome.org/show_bug.cgi?id=690982