handle autofocus like nonce and tabindex for #258

spec.html

@@ -360,6 +360,7 @@ <h4>Global Attributes</h4>
             elements:
           </p>
           <ul>
+            <li><a><code>autofocus</code></a></li>
             <li><a><code>class</code></a></li>
             <li><a><code>data-*</code></a></li>
             <li><a><code>dir</code></a></li>
@@ -384,13 +385,15 @@ <h4>Attributes common to HTML and MathML elements</h4>
             <dfn class="element-attr no-export">class</dfn>,
             <dfn class="element-attr no-export">style</dfn>,
             <dfn class="no-export"><code>data-*</code></dfn>,
+            <dfn class="element-attr no-export">autofocus</dfn> and
             <dfn class="element-attr no-export">nonce</dfn> and
             <dfn class="element-attr no-export">tabindex</dfn>
             attributes have the same syntax and semantics as defined for
             [^global/id^],
             [^global/class^],
 	    [^html-global/style^],
             <a data-cite="HTML/../#embedding-custom-non-visible-data-with-the-data-*-attributes">data-*</a>,
+            [^htmlsvg-global/autofocus^],
             [^htmlsvg-global/nonce^] and
             [^htmlsvg-global/tabindex^]
             attributes on HTML elements.