Index: source
===================================================================
--- source	(revision 1658)
+++ source	(revision 1659)
@@ -12209,16 +12209,21 @@
    <dd><code title="attr-iframe-name">name</code></dd>
    <dd><code title="attr-iframe-sandbox">sandbox</code></dd>
    <dd><code title="attr-iframe-seamless">seamless</code></dd>
+   <dd><code title="attr-dim-width">width</code></dd>
+   <dd><code title="attr-dim-height">height</code></dd>
    <dt>DOM interface:</dt>
    <dd>
 <pre class="idl">interface <dfn>HTMLIFrameElement</dfn> : <span>HTMLElement</span> {
            attribute DOMString <span title="dom-iframe-src">src</span>;
            attribute DOMString <span title="dom-iframe-name">name</span>;
            attribute DOMString <span title="dom-iframe-sandbox">sandbox</span>;
-           attribute boolean <span title="dom-iframe-seamless">seamless</span>;<!--
+           attribute boolean <span title="dom-iframe-seamless">seamless</span>;
+           attribute long <span title="dom-dim-width">width</span>;
+           attribute long <span title="dom-dim-height">height</span>;
+<!-- XXX we should bring these back since the Window spec has atrophied
   readonly attribute Document <span title="dom-iframe-contentDocument">contentDocument</span>;
-  readonly attribute <span>Window</span> <span title="dom-iframe-contentWindow">contentWindow</span>;-->
-};</pre>
+  readonly attribute <span>Window</span> <span title="dom-iframe-contentWindow">contentWindow</span>;
+-->};</pre>
     <p>Objects implementing the <code>HTMLIFrameElement</code>
     interface must also implement the <code>EmbeddingElement</code>
     interface defined in the Window Object specification. <a
@@ -12586,6 +12591,10 @@
 
 
 
+  <p>The <code>iframe</code> element supports <span>dimension
+  attributes</span> for cases where the embedded content has specific
+  dimensions (e.g. ad units have well-defined dimensions).</p>
+
   <p>An <code>iframe</code> element never has <span>fallback
   content</span>, as it will always create a nested <span>browsing
   context</span>, regardless of whether the specified initial contents