Disambiguate "url" export (#348)

Fixes #347.

Author: foolip

index.bs

@@ -2540,7 +2540,7 @@ navigation status</dfn> struct, which has the following items:
       "<dfn export id="navigation-status-complete"><code>complete</code></dfn>".
     </dd>
 
-  <dt><dfn export id="navigation-status-url">url</dfn></dt>
+  <dt><dfn export for="WebDriver navigation status" id="navigation-status-url">url</dfn></dt>
   <dd>The URL which is being loaded in the navigation</dd>
 </dl>