AudioContext.onerror

[hoch]

This PR resolves #2567.

• Add the onerror event handler under the AudioContext interface.
• Add a step to fire onerror event in the AudioContext constructor steps on the render thread.
• Remove the non-normative notes on the notification being impossible.
• Add a prose to specify the onerror case on a running AudioContext.

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Preview | Diff

[hoch]

@padenot Ready for the first pass. Let me know what you think!

[gsinafirooz]

Hi @padenot; I just wanted to bump this.

[marcoscaceres]

@jernoble, could you take a look at this also by chance?

[hoch]

@padenot It looks like we resolved all discussions so far. Let me know if you have more questions!

[gsinafirooz]

@jernoble, could you take a look at this also by chance?

@jernoble, We'd like to hear your opinion :)