Squelches a warning about missing font-family when dragging the icon

Samples/basic/drag/data/icon.rcss

@@ -19,3 +19,10 @@ icon
     
     drag: clone;
 }
+
+icon:drag
+{
+    /* Since this is an ad-hoc element, we need to define the font face to 
+       avoid runtime warnings about not having a font-family defined       */
+    font-family: Delicious;
+}