The new PidginConversationWindow is using a GtkTreeView for navigation and the drag and drop code is just getting in the way while trying to migrate everything so deleting it now makes it easier to migrate.
Testing Done:
Opened two XMPP conversations, verified drag and drop longer worked and that there were no new compiler warnings.
Reviewed at https://reviews.imfreedom.org/r/1026/
PidginandFinch:ThePimpin' Penguin IM Clients That'reGoodfortheSoul