Converting `#ifdef HAVE_X11` to `#if HAVE_X11` changes the question from "does
this macro exist" to "what is its value", so the definition must actually be in
scope. Doing the conversion without guaranteeing the include turned a silently
inert guard into a hard error:
shell/panelview.h:13: error: 'HAVE_X11' is not defined, evaluates to 0
KDE builds with -Werror=undef, so an undefined macro in #if is fatal. The
previous commit fixed the guard form and introduced this; the transform now
inserts #include <config-X11.h> when it converts a guard in a file that lacks
it.
Verified: panelview.h now carries the include, and a second run is a no-op.
vasilito
270d0c9ff6