Update index.bs

Co-authored-by: Domenic Denicola <[email protected]>

Author: youennf

index.bs

@@ -240,7 +240,7 @@ Similarly, if a web application sets the transform synchronously at creation of
 
 # SFrameTransform # {#sframe}
 
-When the SFrameTransform.constructor() is invoked, run the following steps:
+The <dfn constructor for="SFrameTransform" lt="SFrameTransform(options)"><code>new SFrameTransform(<var>options</var>)</code></dfn> constructor steps are:
 1. Let |transformAlgorithm| be an algorithm which takes a |frame| as input and runs the <a href="#sframe-transform-algorithm">SFrame transform algorithm</a> with |this| and |frame|.
 2. Set |this|.<a href="https://streams.spec.whatwg.org/#generictransformstream-transform">`[[transform]]`</a> to the result of <a href="https://streams.spec.whatwg.org/#transformstream-create">creating a TransformStream</a>, its <a href="https://streams.spec.whatwg.org/#transformstream-create-transformalgorithm">transformAlgorithm</a> set to |transformAlgorithm|.
 3. Let |options| be the method's first argument.