* Add debian/patches/git_stylecontext-make-sure-valid.patch

- patch from upstream git to fix crash with some themes (Closes: #800911)

debian/patches/git_stylecontext-make-sure-valid.patch

@@ -0,0 +1,31 @@
+From bddc524cd84b76d1c25c7700eca9d3a25db30cf6 Mon Sep 17 00:00:00 2001
+From: Benjamin Otte <otte@redhat.com>
+Date: Sat, 10 Oct 2015 23:21:45 +0200
+Subject: stylecontext: Make sure style is valid when looking up style
+ properties
+
+Otherwise, the validation may happen vey automatically some time during
+the style property and that will most likely cause a crash.
+
+https://bugzilla.gnome.org/show_bug.cgi?id=756338
+---
+ gtk/gtkstylecontext.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/gtk/gtkstylecontext.c b/gtk/gtkstylecontext.c
+index 0217d55..5d059a0 100644
+--- a/gtk/gtkstylecontext.c
++++ b/gtk/gtkstylecontext.c
+@@ -1557,6 +1557,9 @@ _gtk_style_context_peek_style_property (GtkStyleContext *context,
+ 
+   priv = context->priv;
+ 
++  /* ensure the style cache is valid by forcing a validation */
++  gtk_style_context_lookup_style (context);
++
+   key.widget_type = widget_type;
+   key.pspec = pspec;
+ 
+-- 
+cgit v0.11.2
+