[gnome-boxes] build: Require Vala >= 0.28.0.16

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 1feb0e6a5ac73bf20bc9ee0bdac73773dae3f86c
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Wed May 27 08:03:27 2015 +0200

    build: Require Vala >= 0.28.0.16
    
    GTK+'s VAPI has changed and build is broken against latest Vala until we
    adapt to latest Gtk+ VAPI and we can't adapt to that change while
    maintaining compatibility with older Vala. Hence this change.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=749914

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 4256412..f3b3ba3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -132,7 +132,7 @@ else
 fi
 AM_CONDITIONAL([HAVE_OVIRT], [test "x$have_govirt" = "xyes"])
 
-VALA_CHECK([0.24.0.65], [
+VALA_CHECK([0.28.0.16], [
   gdk-pixbuf-2.0
   glib-2.0
   gtk+-3.0