Differences from 6u1:
- we do accept non-synthetic configure events for NO_WM (this is fix for
6434227 - Popup menus when rendered on X Client can't be selected w/ mouse).
- all made final (just to make code clearer :)
- getInsetsFromProp() now tries to read extents from all atoms we know
not only for enlightenment and compiz) and it returns Insets, not boolean.
- readInsetsFromProp() returns Insets and (in fact) it is a renamed
version of XNETProtocol.calcWMExtents() which was removed from XNETProtocol.
- also I've moved requestWMExtents() from XNETProtocol to XWM to keep
all extents-related code in one place.
there were some typos in atoms' names so now we use constants.