[gtksourceview] Only build with GSEAL when it makes sense

[Jesse van den Kieboom <jessevdk src gnome org>]

commit faf92f8ad60e8f583bfab71e94cbb80d68908ed9
Author: Jesse van den Kieboom <jessevdk gnome org>
Date:   Fri Jun 4 22:37:18 2010 +0200

    Only build with GSEAL when it makes sense

 configure.ac |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index ef1c435..f50d8b8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -58,14 +58,18 @@ AC_ARG_ENABLE(deprecations,
               [enable_deprecations=$enableval], [])
 
 if test "$enable_deprecations" = "yes"; then
-   DISABLE_DEPRECATED_CFLAGS="\
--DGSEAL_ENABLE \
+	DISABLE_DEPRECATED_CFLAGS="\
 -DG_DISABLE_DEPRECATED \
 -DGDK_DISABLE_DEPRECATED \
 -DGTK_DISABLE_DEPRECATED \
 -DGDK_PIXBUF_DISABLE_DEPRECATED \
 -DGNOME_DISABLE_DEPRECATED"
-   AC_SUBST(DISABLE_DEPRECATED_CFLAGS)
+
+	if $PKG_CONFIG --atleast-version 2.90 $GTK_REQUIRED; then
+		DISABLE_DEPRECATED_CFLAGS="$DISABLE_DEPRECATED_CFLAGS -DGSEAL_ENABLE"
+	fi
+
+	AC_SUBST(DISABLE_DEPRECATED_CFLAGS)
 fi
 
 PKG_CHECK_EXISTS([gtk+-3.0 >= 2.90],