[gnome-flashback] remove unused HAVE_XRANDR15 define

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 5e3a6f9a3a906db01cce58b89975e5dbf27216b7
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Oct 31 23:41:35 2019 +0200

    remove unused HAVE_XRANDR15 define

 configure.ac | 8 --------
 1 file changed, 8 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 7465ead..e70b672 100644
--- a/configure.ac
+++ b/configure.ac
@@ -277,14 +277,6 @@ PKG_CHECK_EXISTS([pango >= 1.44.0],
                  AC_DEFINE([HAVE_PANGO144], [1],
                            [Define if Pango is 1.44.0 or newer]))
 
-dnl **************************************************************************
-dnl Check if we have XRandR 1.5 or newer
-dnl **************************************************************************
-
-PKG_CHECK_EXISTS([xrandr >= 1.5.0],
-                 AC_DEFINE([HAVE_XRANDR15], [1],
-                           [Define if XRandR is 1.5.0 or newer]))
-
 dnl **************************************************************************
 dnl Systemd session
 dnl **************************************************************************