window: Update view and selection only on map
In constructed(), the window object won’t be ready yet. And if we try to select a chat, it may result in chatty-application trying to open the chat. It will result in g_application_activate() which will try to create the window again resulting in an infinite loop
Fix it by handling them on map(), so that these actions will be done only on gtk_window_present().
Fixes #604 (closed)