Add HTML-in-Canvas APIs

source

@@ -66274,6 +66274,7 @@ interface <dfn interface>CanvasRenderingContext2D</dfn> {
 <span>CanvasRenderingContext2D</span> includes <span>CanvasDrawPath</span>;
 <span>CanvasRenderingContext2D</span> includes <span>CanvasUserInterface</span>;
 <span>CanvasRenderingContext2D</span> includes <span>CanvasText</span>;
+<span>CanvasRenderingContext2D</span> includes <span>CanvasDrawElement</span>;
 <span>CanvasRenderingContext2D</span> includes <span>CanvasDrawImage</span>;
 <span>CanvasRenderingContext2D</span> includes <span>CanvasImageData</span>;
 <span>CanvasRenderingContext2D</span> includes <span>CanvasPathDrawingStyles</span>;
@@ -66393,6 +66394,12 @@ interface mixin <dfn interface>CanvasText</dfn> {
   <span>TextMetrics</span> <span data-x="dom-context-2d-measureText">measureText</span>(DOMString text);
 };
 
+interface mixin <dfn interface>CanvasDrawElement</dfn> {
+  // drawing elements
+  undefined <span data-x="dom-context-2d-drawElement">drawElement</span>(<span>Element</span> element, unrestricted double x, unrestricted double y);
+  undefined <span data-x="dom-context-2d-drawElement">drawElement</span>(<span>Element</span> element, unrestricted double x, unrestricted double y, unrestricted double w, unrestricted double y);
+};
+
 interface mixin <dfn interface>CanvasDrawImage</dfn> {
   // drawing images
   undefined <span data-x="dom-context-2d-drawImage">drawImage</span>(<span>CanvasImageSource</span> image, unrestricted double dx, unrestricted double dy);
@@ -70681,6 +70688,55 @@ try {
 
   </div>
 
+
+  <h6>Drawing elements</h6>
+
+  <dl class="domintro">
+   <dt><code data-x=""><var>context</var>.<span subdfn data-x="dom-context-2d-drawElement">drawElement</span>(<var>image</var>, <var>x</var>, <var>y</var>)</code></dt>
+   <dt><code data-x=""><var>context</var>.<span data-x="dom-context-2d-drawElement">drawElement</span>(<var>image</var>, <var>x</var>, <var>y</var>, <var>w</var>, <var>h</var>)</code></dt>
+
+   <dd>
+    <p>Draws the given element onto the canvas. Throws a <code>TypeError</code> if the element isn't
+    a descendant of the canvas.</p>
+   </dd>
+  </dl>
+
+  <div w-nodev>
+
+  <p>Objects that implement the <code>CanvasDrawElement</code> interface have the <dfn method
+  for="CanvasDrawElement"><code data-x="dom-context-2d-drawElement">drawElement()</code></dfn>
+  method to draw elements.</p>
+
+  <p>When the <code data-x="dom-context-2d-drawElement">drawElement()</code> method is invoked, the user
+  agent must run these steps:</p>
+
+  <ol>
+   <li><p>👋 Let <var>element</var> be the first argument.</p>
+
+   <li><p>If any of the arguments are infinite or NaN, then return.</p></li>
+
+   <li><p>Let <var>usability</var> be the result of 👋.</p></li>
+
+   <li><p>If <var>usability</var> is <i>bad</i>, then return (without drawing anything).</p></li>
+
+   <li><p>👋 Update the rendering without painting.</p></li>
+   <!-- If w/h arguments are given, should that be an input to layout here?
+        And if not, is the layout totally unconstrained, infinite width?? -->
+
+   <li><p>👋 Let <var>layoutBox</var> be <var>element</var>'s CSS layout box.</p></li>
+
+   <li><p>If not specified, the <var>w</var> and <var>h</var> arguments must default to the width
+   and height of <var>layoutBox</var>.</p></li>
+
+   <li><p>If either <var>w</var> or <var>h</var> are zero, then return.</p></li>
+
+   <li><p>👋 Paint <var>element</var> to the specified rectangular area without using any
+   <span>CORS-cross-origin</span> data.</p></li>
+  </ol>
+
+  </div>
+
+
   <h6>Drawing images</h6>
 
   <p>Objects that implement the <code>CanvasDrawImage</code> interface have the <dfn method