[gtksourceview] Allow for multiple GDK backends

[Philip Chimento <pchimento src gnome org>]

commit 194d40ed2e6e27889b201b4c84997b1e7075a3a5
Author: Philip Chimento <philip chimento gmail com>
Date:   Tue Nov 22 13:05:08 2011 +0100

    Allow for multiple GDK backends
    
    In GDK > 3.0, multiple backends can be built. The pkg-config
    variable that tells the backend is now called 'targets' instead of
    'target'. To determine whether to build for OS X, configure now
    needs to use the GTK_CHECK_BACKENDS macro supplied with GTK, as
    described in the migration guide:
    http://developer.gnome.org/gtk3/3.3/ch25s02.html

 configure.ac |    9 +--------
 1 files changed, 1 insertions(+), 8 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 7d4a17f..3d88fe5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -84,14 +84,7 @@ AM_CONDITIONAL([ENABLE_PROVIDERS], [ test "$enable_providers" = "yes" ])
 
 dnl check for native osx
 AC_MSG_CHECKING([for native Mac OS X])
-
-gdk_windowing=`$PKG_CONFIG --variable=target gdk-3.0`
-
-if test "$gdk_windowing" = "quartz"; then
-	os_osx=yes
-else
-	os_osx=no
-fi
+GTK_CHECK_BACKEND([quartz], [3.0.0], [os_osx=yes], [os_osx=no])
 AC_MSG_RESULT([$os_osx])
 AM_CONDITIONAL([OS_OSX], [ test "$os_osx" = "yes" ])