[Etoys] Window events

[Bert Freudenberg]

To solve trac #3062, Ian added VM support for a close window event.  
Now we need image code for this.

The original support code is here:

ftp://smalltalkconsulting.com/experimental/Ffenestri/Ffenestri-b-4- 
Events-Morphic.1.cs

it basically adds a windowIndex field to each MorphicEvent plus a new  
event class (WindowEvent). The window index would be used to  
distinguish mouse events in different windows (so it is constant for  
us, we only have one OS window). The new WindowEvent would be what we  
are interested in, as we get this when the etoys activity is closed.

Does anybody see a downside to including that changeset verbatim? I  
haven't compared it to the current code in the image in detail yet.  
It does a bit more than we need right now, sow we could strip it  
down, OTOH, I suspect this will land in the the squeak.org version  
sooner or later so having it should not be bad.

Opinions?

- Bert -