Some of them are unused, some of them were missing. Also add a list of
the available debug macros.

Fixes ArcticaProject/nx-libs#825

no functional change

no functional change

turns out that our composite is much newer than xorg 6.9/7.0...

we don't have that...

  commit 312910b4e34215aaa50fc0c6092684d5878dc32f
  Author: Chase Douglas <chase.douglas@canonical.com>
  Date:   Wed Apr 18 11:15:40 2012 -0700

    Update currentTime in dispatch loop

    A request, like input device grabs, may check a request timestamp
    against currentTime. It is possible for currentTime to lag a previously
    sent event timestamp. If the client makes a request based on such an
    event timestamp, the request may fail the validity check against
    currentTime unless we always update the time before processing the
    request.
Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

XGetWMName returns non-zero on success

The result was that no window names were displayed in DEBUG_TREE remote windows
tree output.

scope improvements, use fprintf for indentation instead of loops.

so hide it behind that define

Attributes GH PR #842: https://github.com/ArcticaProject/nx-libs/pull/842

nxagentRenderTrap is rather old. This flag is set when internal pixmap
creation returns a pixmap with depth 0. Following that the RENDER
extension is effectively disabled. However: there's no code that could
create a pixmap with depth 0, so let's simplify our code by removing
nxagentRenderTrap altogether.

Fixes ArcticaProject/nx-libs#841

Attributes GH PR #844: https://github.com/ArcticaProject/nx-libs/pull/844