It's unnecessary, and only adds visual noise; we have been fairly
inconsistent in the past, but the semi-colon-less version clearly
dominates in the code base.
https://bugzilla.gnome.org/show_bug.cgi?id=669355
GListModel is an interface that represents a dynamic list of GObjects.
Also add GListStore, a simple implementation of GListModel that stores
all objects in memory, using a GSequence.
https://bugzilla.gnome.org/show_bug.cgi?id=729351