[mediacapture-main] Make fitness distance a SHOULD instead of MAY on device delection. (#735)

jan-ivar has just created a new issue for https://github.com/w3c/mediacapture-main:

== Make fitness distance a SHOULD instead of MAY on device delection. ==
I think we should strengthen this to ensure web compat around constraints use in `getUserMedia`.

Sites are going to do things like:
```js
await navigator.mediaDevices.getUserMedia({video: {deviceId: deviceFromLastVisitId, height: 1080}});
```
...and expect comparable results across browsers (same device if available, or comparable 1080p cam if not).

I suspect implementations already comply, but right now this hinges on a **MAY** in the spec which seems too weak.

On the **MAY**: Firefox is the lone implementation to allow users to override the (ideal) device choice in its permission prompt, but I think that's a valid exception (if the user explicitly chose a device, the site should probably honor it!)

But that shouldn't stand in the way of improving web compat of the automated device selection process where the user does _not_ override.

So I'm propose a **SHOULD** instead of **MAY** here, with a mention of _"user preference"_ as an example of valid exception.

Please view or discuss this issue at https://github.com/w3c/mediacapture-main/issues/735 using your GitHub account


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Received on Tuesday, 6 October 2020 16:09:15 UTC