Changeset [252b8f5ca5231c29bbe2a3c71561fabad3f81749] by Alexander Ljungberg

Fixed: [CPApp windows] contained nil.

Before this fix, CPApp tried to add nil to its internal list of windows, even that nil should not be added to a CPArray. Second, that nil was actually returned by [CPApp windows] rather than an expected list of only CPWindow instances.

This fix makes [CPApp windows] return only actual windows, replaces the internal _windows[0] placeholder with CPNull, and ensures this CPNull is never actually exposed outside of the class.
https://github.com/cappuccino/cappuccino/commit/252b8f5ca5231c29bbe...