[PATCH weston] compositor: add a mouse motion binding type

[Bill Spitzak]

Kristian Høgsberg wrote:

> I'm not sure if this is what Bill is getting at, but there is a
> problem with just unconditionally triggering motion bindings.  If
> you're moving or resizing a window and move the pointer to the corner,
> you don't want to make that trigger an expose effect or such.

I was completely confusing corners of surfaces with corners of outputs, 
sorry. He is talking about fixed locations on the screen that are 
usually called "hot corners" and other terms.

I think however that "hot corners" like he is describing might be better 
described as special invisible surfaces. They could be implemented by 
clients as well as by the shell, and could be subject to stacking order. 
It would also make it obvious that drags do not trigger the hot corner 
effect, though it may be triggered after the mouse is released.