OfflineAudioContext: closes and fires a statechange event when rendering is done

[gabrielsanbrito]

Describe the issue

After OfflineAudioContext.startRendering() finishes and the returned promise resolves, the context transitions to the "closed" state and a statechange is fired. Apparently, all the major browser engines implement this behavior. I personally verified Blink and Gecko, but WebKit also seems to be implementing something similar.

This behavior is not in the specification. The specification only says here that:

4. Once the rendering is complete, queue a media element task to execute the following steps:
   1. Resolve the promise created by startRendering() with [[rendered buffer]].
   2. Queue a media element task to fire an event named complete at the OfflineAudioContext using OfflineAudioCompletionEvent whose renderedBuffer property is set to [[rendered buffer]].

Where Is It

OfflineAudioContext.startRendering()

Additional Information

You can use this demo page to test it out.