Fix or style-offset calculation in back

[Wolfgang Lux]

The last change for the style-offset calculation in back unfortunately
made things worse than before (sorry Fred). In particular, the bottom
offset was too large. Here is a patch that should hopefully get
style-offset calculation right. I've tested it with a few window  
managers
(Apple's quartz-wm, WindowMaker, and mwm from lesstif, which does double
reparenting) and things now work correctly for all of them. As a small
bonus, the patch also fixes the use of an uninitialized variable in an
NSLog call.

Wolfgang

style-offset.patch
Description: Binary data