Merge pull request w3c#281 from w3c/remove-LegacyArrayClass

[geometry-1] Remove LegacyArrayClass from DOMRectList. w3c#280

Author: dirkschulze

geometry/Overview.bs

@@ -412,7 +412,6 @@ steps:
 <h2 id=DOMRectList>The DOMRectList interface</h2>
 
 <pre class=idl>
-[LegacyArrayClass]
 interface DOMRectList {
     readonly attribute unsigned long length;
     getter DOMRect? item(unsigned long index);