We switched from using the window icon to using the associated
application's icon; however when we create the window list item
from a handler to the 'window-added' signal, the association of
window and application might not exist yet, as WindowTracker uses
the same signal to create the association. Use connect_after()
for creating the window list item to make sure that WindowTracker's
signal handler has run already.
https://bugzilla.gnome.org/show_bug.cgi?id=695389