cssvalue: Pass property ID to transition function

This is to allow animating arrays properly. I'm not really thrilled
about this solution (we leak propertys into the values again...), but
it's the best I can come up with - I prefer it to having N different
array types...

gtk/gtkcssarrayvalue.c

@@ -95,6 +95,7 @@ gtk_css_value_array_equal (const GtkCssValue *value1,
 static GtkCssValue *
 gtk_css_value_array_transition (GtkCssValue *start,
                                 GtkCssValue *end,
+                                guint        property_id,
                                 double       progress)
 {
   return NULL;