[evolution-data-server/gnome-2-32] Bug 637916 - configure.ac with_nspr_includes test is incorrect

[Matthew Barnes <mbarnes src gnome org>]

commit da42efc59d9541c4b1f098bbf267210630e17ccd
Author: Stef Walter <stefw collabora co uk>
Date:   Mon Dec 27 08:17:25 2010 -0500

    Bug 637916 - configure.ac with_nspr_includes test is incorrect

 configure.ac |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index dd8acf5..88b6811 100644
--- a/configure.ac
+++ b/configure.ac
@@ -614,7 +614,9 @@ dnl check if pkg-config files exist (which are only shipped by distributions, no
 	dnl ******************
 		AC_MSG_CHECKING([for Mozilla nspr4 includes])
 			CPPFLAGS_save="$CPPFLAGS"
-			CPPFLAGS="$CPPFLAGS -I$with_nspr_includes"
+			if test -n "$with_nspr_includes"; then
+				CPPFLAGS="$CPPFLAGS -I$with_nspr_includes"
+			fi
 
 			AC_CHECK_HEADERS(nspr.h prio.h,
 			[moz_nspr_includes="yes"],[moz_nspr_includes="no"])