Add empty RTCSetParameterOptions dict as argument to setParameters

[fippo]

Both are defined as empty in order to allow webrtc-extensions to extend them which is done in
w3c/webrtc-extensions#167

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[Orphis]

Add an export?

[dontcallmedom]

(not needed - as an IDL term, this gets exported automatically)

[jan-ivar]

This extends the setParameters method with a feature/encoding-specific argument:

await setParameters(params, [{keyFrame: true}, {keyFrame: false}]);

This violates § 6.4. Accept optional and/or primitive arguments through dictionaries, as well as my understanding that we agreed to add a feature-agnostic options object:

Promise<undefined> setParameters(RTCRtpSendParameters parameters,
                                 optional setParametersOptions = {});

Webrtc-extensions would then define the rest, with a final shape e.g. maybe like this:

await setParameters(params, {encodingOptions: [{keyFrame: true}, {keyFrame: false}]});

or e.g. maybe this?

await setParameters(params, {encodingKeyframes: [true, false]});

[fippo]

Updated (with slight changes).

Can you please explain what future extensions you see and how they are not specific to the encodings and would not fit into an array?

[jan-ivar]

I don't have a specific extension in mind, but to exempt ourselves from following § 6.4. Accept optional and/or primitive arguments through dictionaries, I think would require an argument that we would never add any future options that aren't encoding-related. Since we have per-header and per-codec parameters, why paint ourselves in that corner?

[fippo]

hrm... any idea why it shows up like this even though it is defined in the same section-h2-h3 as the previous dict?