[gitg] Only build with GSEAL_ENABLE on >= 2.21

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

commit 65a888a43358480029e4bc6ec69582a87d713219
Author: Jesse van den Kieboom <jesse vandenkieboom epfl ch>
Date:   Wed Jun 9 20:45:32 2010 +0200

    Only build with GSEAL_ENABLE on >= 2.21

 configure.ac |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index e8a45a1..e2a45d0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -102,7 +102,15 @@ fi
 AM_CONDITIONAL(BUILD_SPINNER, test "$gtkatleast" = "no")
 if test "$gtkatleast" = "no"; then
 	AC_DEFINE([BUILD_SPINNER],[1],[Whether to use GitgSpinner instead of GtkSpinner])
+fi
+
+if $PKG_CONFIG --atleast-version 2.21.0 $GTK_REQUIRED; then
+	gtkatleast=yes
 else
+	gtkatleast=
+fi
+
+if test "$gtkatleast" = "yes"; then
 	DISABLE_DEPRECATED_CFLAGS="$DISABLE_DEPRECATED_CFLAGS -DGSEAL_ENABLE"
 fi