Drop local definition of now fixed HTML anchors

Definitions fixed upstream so local definitions are no longer needed:
whatwg/html#8736

Author: tidoust

index.src.html

@@ -35,9 +35,6 @@
 
 <pre class='anchors'>
 spec: html; urlPrefix: https://html.spec.whatwg.org/multipage/;
-    type: typedef; text: CanvasImageSource; url: canvas.html#canvasimagesource
-    for: CanvasDrawImage;
-        type: method; text: drawImage(); url: canvas.html#dom-context-2d-drawimage
     for: ImageBitmap;
         type: dfn; text: bitmap data; url: imagebitmap-and-animations.html#concept-imagebitmap-bitmap-data
     for: Canvas;