Add default dictionary value (#936)

saschanaz · dbaron · commit edf93aefc5c4 · 2019-08-21T22:35:09.000-07:00
Required after whatwg/webidl#750.
diff --git a/css-typed-om/Overview.bs b/css-typed-om/Overview.bs
@@ -2477,7 +2477,7 @@ This list is the object's [=values to iterate over=].
     };
 
     [Exposed=(Window, Worker, PaintWorklet, LayoutWorklet),
-     Constructor(DOMMatrixReadOnly matrix, optional CSSMatrixComponentOptions options)]
+     Constructor(DOMMatrixReadOnly matrix, optional CSSMatrixComponentOptions options = {})]
     interface CSSMatrixComponent : CSSTransformComponent {
         attribute DOMMatrix matrix;
     };
