We can use the new motion event controller that
was introduced for this purpose.

We can just use a multipress gesture for this purpose.

We can use the new motion event controller for this.

This lets us avoid legacy event signals here.

This can serve as a replacement for the legacy
event signals for enter/leave/motion notify.

This is an attempt to see how much work is needed to
reproduce entry icons by just putting an entry and images
in a box, with some css glue.

Replace the motion_notify handler by a drag gesture.

This makes drag icons set from icon names come out
at a size that it large enough to not disappear under
the drag cursor.

This lets us use the new icon-size machinery to
ensure we don't have tiny drag icons when using
named icons.

Instead, pass the actions as part of gdk_drag_begin() and insist DND is
always managed.

A new side effect is that gdk_drag_begin() can now return %NULL.