ibus: Check window parent process's name for ibus-daemon to determine window type assignment

I haven't observed any performance hit this way, but I'd like others testing to verify.

This is an alternative to handling ibus popups (the original solution is to be reverted by #83)

Note:  I see this as a temporary workaround only - in Cinnamon 2.0, we will implement a full clutter-based popup, but to do that we must change how we currently handle input method switching, which will be easy when we fork gnome-settings-daemon (the current upstream gnome method is superior - ubuntu uses scripts to accomplish this right now)