Update MediaStreamTrackProcessor spec_url and mark Chrome constructor support as partial

[jan-ivar]

Summary

• Have MediaStreamTrackProcessor members inherit partial support in chrome, for visibility
• Add mdn links to VideoTrackGenerator

Test results and supporting details

npm test verified JSON, but complains of missing mdn links for VideoTrackGenerator (coming in mdn/content#39124).

couldn't get npm run stats to work, so hopefully things look OK.

Spec: https://w3c.github.io/mediacapture-transform/

[caugner]

npm test verified JSON, but complains of missing mdn links for VideoTrackGenerator (coming in mdn/content#39124).

Note: We don't add mdn_urls to BCD before the corresponding pages are in content. Once a page with browser-compat frontmatter lands, the mdn_url field of the referenced BCD feature will be populated automatically (cf. this commit).

[caugner]

Let's make the notes more concise.

Did you want to add similar notes to VideoTrackGenerator?

[jan-ivar]

Did you want to add similar notes to VideoTrackGenerator?

No, since Chrome does not implement VideoTrackGenerator. When they do it will hopefully be on DedicatedWorker.

[caugner]

The spec defines exposure on the interface, not on its members, so I don't think it's right to set partial_implementation: true on the members, especially not on the readable property.

I acknowledge that it can be confusing that this limitation is not visible on the MediaStreamTrackProcessor constructor page, but I don't think updating the data like this is the right approach. Instead, I'm thinking that the BCD tables on MDN could include rows for the parent feature, while highlighting the feature corresponding to the current page.

I added this issue to the agenda of the next BCD meeting, so that we decide how to proceed.

[caugner]

I added this issue to the agenda of the next BCD meeting, so that we decide how to proceed.

We discussed this in today's BCD meeting, and for now we accept (but don't require) partial_implementation: true on the constructor in this case, but not on the other members (here: readable).

[github-actions]

Tip: Review these changes grouped by change (recommended for most PRs), or grouped by feature (for large PRs).