invalidate MWindowPropertyCache::window_type if the WINDOW_TYPE changes
invalidate MWindowPropertyCache::window_type if the WINDOW_TYPE changes

fixes 5137bfffd10e04466d9615d5b68426677941e3b8

nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor