Allow <bnf-opt> to surround the optional grammar component.

jyasskin · jyasskin · commit 4b59edfd060c · 2014-03-09T11:55:14.000-07:00
diff --git a/grammar.html b/grammar.html
@@ -69,7 +69,7 @@
 
 <!-- BNF optional element -->
 <polymer-element name="bnf-opt" noscript>
-  <template><sub>opt</sub></template>
+  <template><content></content><sub>opt</sub></template>
 </polymer-element>
 
 <!-- Grammar terms
