css: Tabs to spaces
server: Add a missing line to syncDrawTree
server: Remove some complicated processing related to PointerRoot

Keyboard focus has a weird quirk, which is that with the PointerRoot
focus mode, the pointer and keyboard focus are the exact same. This
behavior is part of the server, which allows it to run correctly without
a window manager.

This behavior is, today, considered a misfeature. To simplify the code
of our fake X server, just kill it.
server: Remove support for FocusRevertTo / PointerRoot in general

RevertToParent is really the only behavior that makes sense.
server: Clean up _setInputFocus

Remove the client parameter, and pass the server window in directly.

Incidentally, this also means that you can't change the input focus to
null. This was long-considered a bug in the X server protocol, and users
should instead set the input focus to the root window.
server: Set the input focus to the root window by default