Meta: add definition metadata for the nonce="" attribute

Helps with w3c/webappsec-csp#329.

source

@@ -7113,10 +7113,10 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
 
   <h4>Nonce attributes</h4>
 
-  <p>A <dfn data-export="" data-x="attr-nonce">nonce</dfn> content attribute represents a
-  cryptographic nonce ("number used once") which can be used by <cite>Content Security Policy</cite>
-  to determine whether or not a given fetch will be allowed to proceed. The value is text. <ref
-  spec="CSP"></p>
+  <p>A <dfn data-export="" data-x="attr-nonce" data-dfn-type="element-attr"
+  data-dfn-for="htmlsvg-global">nonce</dfn> content attribute represents a cryptographic nonce
+  ("number used once") which can be used by <cite>Content Security Policy</cite> to determine
+  whether or not a given fetch will be allowed to proceed. The value is text. <ref spec="CSP"></p>
 
   <p>Elements that have a <code data-x="attr-nonce">nonce</code> content attribute ensure that the
   crytographic nonce is only exposed to script (and not to side-channels like CSS attribute
@@ -7134,9 +7134,10 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
    </dd>
   </dl>
 
-  <p>The <dfn id="dom-noncedelement-nonce"><code
-  data-x="dom-HTMLOrSVGElement-nonce">nonce</code></dfn> IDL attribute must, on getting, return the
-  value of this element's <span>[[CryptographicNonce]]</span>; and on setting, set this element's
+  <p>The <dfn id="dom-noncedelement-nonce" data-export="" data-dfn-type="attribute"
+  data-dfn-for="HTMLOrSVGElement"><code data-x="dom-HTMLOrSVGElement-nonce">nonce</code></dfn> IDL
+  attribute must, on getting, return the value of this element's
+  <span>[[CryptographicNonce]]</span>; and on setting, set this element's
   <span>[[CryptographicNonce]]</span> to the given value.</p>
 
   <p class="note" id="nonce-does-not-update-dom">Note how the setter for the <code
@@ -121089,6 +121090,7 @@ INSERT INTERFACES HERE
   Andry Rendy,
   Andy Earnshaw,
   Andy Heydon,
+  Andy Paicu,
   Andy Palay,
   Anjana Vakil,
   Ankur Kaushal,