Event redirection issue: determining the type of triggered grabs

[Deron Johnson]

>>2. If an Enter event with NotifyGrab is generated and the entered
>>   window is the PRW, a default button grab has triggered. Fetch
>>   the 3D grab object from the last motion event.
> 
> 
> If the pointer is already in the PRW, no enter event will be generated.

Rats. You're right. DoEnterLeaveEvents has code which skips the sending
of an Enter event if the grabbed window is the current sprite window.

> Is this an issue?  

Yes. I will need the Enter event on the activate grab to ALWAYS be
generated. It looks like we might have to add a "force" argument
to DoEnterLeaveEvents. Any other ideas?