Bug Fix: MultiColumnList::setItem was setting owner on new item without checking new item was valid.
Bug Fix: MultiColumnList::setItem was setting owner on new item without checking new item was valid.

cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two