This commit is related to the bug #683420.
Commit 1532d7ef forgot to actually define HAVE_CUPS_1_6 when building against CUPS 1.6 https://bugzilla.gnome.org/show_bug.cgi?id=683441
1532d7ef
PpMaintenanceCommand object contains asynchronous method which executes given CUPS maintenance command (e.g. "AutoConfigure"). (#683229)