that these directories will be conditionally removed (based on reference
counts), regardless of the value of PKG_CONFIG. Bump the PKGREVISION
for packages that were modified as a result.
theme-dirs installs a set of shared directories used by GTK2+ (gtk2-engines)
and other GNOME packages (such as metacity and gnome-themes). It is useful
to simplify PLIST handling in other packages.