[gnome-shell] theme-node: fix support for box-shadow: none

[Cosimo Cecchi <cosimoc src gnome org>]

commit 0b219bf8cba354ced8f97a12b5f78e6a720f005f
Author: Cosimo Cecchi <cosimo endlessm com>
Date:   Thu Jun 20 14:51:33 2013 -0700

    theme-node: fix support for box-shadow: none
    
    We currently don't parse "box-shadow: none", despite being valid CSS.
    Fix it so that it uses the default shadow values.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=702782

 src/st/st-theme-node.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/st/st-theme-node.c b/src/st/st-theme-node.c
index e4eddcf..5250e8a 100644
--- a/src/st/st-theme-node.c
+++ b/src/st/st-theme-node.c
@@ -3056,6 +3056,10 @@ parse_shadow_property (StThemeNode       *node,
    */
   for (term = decl->value; term; term = term->next)
     {
+      /* if we found "none", we're all set with the default values */
+      if (term_is_none (term))
+        return VALUE_FOUND;
+
       if (term->type == TERM_NUMBER)
         {
           gdouble value;