Pull some common options as defaults and only change them if needed

configure.in

@@ -1544,14 +1544,16 @@ dnl The following is a list of supported systems.
 dnl Sequential to keep the logic very simple
 dnl These values may be checked and reset later.
 dnl ===================================================================
+#defaults unless the os test overrides this:
+test_cairo=yes
+test_randr=yes
+
 case "$build_os" in
     solaris*)
         test_gtk=yes
-        test_cairo=yes
         build_gstreamer=yes
         test_kde=yes
         test_cups=yes
-        test_randr=yes
         test_freetype=yes
         _os=SunOS
         AC_PATH_PROG( GNUTAR, gtar,,$PATH:/usr/sfw/bin)
@@ -1581,30 +1583,29 @@ case "$build_os" in
         ;;
     linux-gnu*|k*bsd*-gnu*)
         test_gtk=yes
-        test_cairo=yes
         build_gstreamer=yes
         test_kde=yes
         test_kde4=yes
         test_cups=yes
-        test_randr=yes
         test_freetype=yes
         test_unix_quickstarter=yes
         _os=Linux
         ;;
     gnu)
+        test_randr=no
+        test_cairo=no
         test_cups=no
         _os=GNU
         ;;
     cygwin*) # Windows
         test_cups=no
-        test_cairo=yes
+        test_randr=no
         test_freetype=no
         _os=WINNT
         ;;
     darwin*) # Mac OS X
         test_cups=yes
         test_gtk=yes
-        test_cairo=yes
         test_randr=no
         test_freetype=no
         _os=Darwin
@@ -1615,21 +1616,19 @@ case "$build_os" in
       fi
         ;;
     os2*)
-        test_x=no
         test_cups=no
         test_randr=no
         test_gtk=no
+        test_cairo=no
         test_freetype=no
         _os=OS2
         ;;
     freebsd*)
         test_gtk=yes
-        test_cairo=yes
         build_gstreamer=yes
         test_kde=yes
         test_kde4=yes
         test_cups=yes
-        test_randr=yes
         test_freetype=yes
         AC_MSG_CHECKING([the FreeBSD operating system release])
         if test -n "$with_os_version"; then
@@ -1654,17 +1653,16 @@ case "$build_os" in
         ;;
     osf)
         test_cups=no
+        test_cairo=no
         test_randr=no
         _os=OSF1
         ;;
     *netbsd*)
         test_gtk=yes
-        test_cairo=yes
         build_gstreamer=yes
         test_kde=yes
         test_kde4=yes
         test_cups=yes
-        test_randr=yes
         test_freetype=yes
         PTHREAD_CFLAGS="-pthread"
         PTHREAD_LIBS="-pthread -lpthread"
@@ -1673,18 +1671,16 @@ case "$build_os" in
     aix*)
         test_cups=no
         test_randr=no
+        test_cairo=no
         test_freetype=yes
         PTHREAD_LIBS=-pthread
         _os=AIX
         ;;
     openbsd*)
-        test_x=yes
         test_gtk=yes
-        build_cairo=yes
         test_kde=yes
         test_cups=yes
         test_freetype=yes
-        test_randr=yes
         PTHREAD_CFLAGS="-pthread -D_THREAD_SAFE"
         PTHREAD_LIBS="-pthread"
         _os=OpenBSD