On button-release, a threshold is used to determine if the gesture
should be considered a click and thus ignored. While the drag is
active though, the controlled actor is dragged immediately. As a
result, dragging by a tiny amount does not trigger a snap back when
the action is interpreted as a click. As a fix, do not update the
dragged actor's position until the same threshold is passed.
https://bugzilla.gnome.org/show_bug.cgi?id=640494
eb8fc738af