Implement Ended media attribute
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This PR should implement:
* New method `HTMLMediaElement::earliest_possible_position()` for the [earliest possible position](https://html.spec.whatwg.org/multipage/media.html#earliest-possible-position)
* `Ended` attribute following https://html.spec.whatwg.org/multipage/media.html#ended-playback
* Queue steps for when the playback position reaches the end
This PR contains placeholders for the following issues (I can rebase changes after the corresponding PRs get merged)
- #22321 (Define the Loop attribute)
- #22293 (To identify playback direction. Either forwards or backwards)
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- [x] These changes fix#22294.
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Based on https://bugzilla.mozilla.org/show_bug.cgi?id=1348519#c6 and
https://github.com/w3c/csswg-drafts/issues/3201:
Currently grid-template-rows/columns interpolate “per computed value”, which
means that if the number of tracks differs, or any track changes to/from a
particular keyword value to any other value, or if a line name is added/removed
at any position, the entire track listing is interpolated as “discrete”.
But we "agree" with two more granular options:
1. Check interpolation type per track, rather than for the entire list, before
falling back to discrete. I.e. a length-percentage track can animate between
two values while an adjacent auto track flips discretely to min-content.
2. Allow discrete interpolation of line name changes independently of track
sizes.
Besides, for the repeat() function, it's complicated to support interpolation
between different repeat types (i.e. auto-fill, auto-fit) and different repeat
counts, so we always fall-back to discrete if the first parameter of repeat()
is different.
Differential Revision: https://phabricator.services.mozilla.com/D16129
Implement DOM APIs for ChannelSplitterNode
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Based on #21591. Fixes#21558. I tried to update the expected results for WPT using "./mach update-wpt"; let me know if I got something wrong.
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- [ ] These changes do not require tests because ___
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Remove trailing ? when updating URLSearchParams
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- [x] These changes fix#22639
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Expose TextTrack.activeCues
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- [X] These changes fix#22675
This only exposes the `activeCues` property to make sure that `/html/semantics/embedded-content/media-elements/track/track-element/track-active-cues.html` timeouts consistently.
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HTMLMediaElement backoff protocol and other improvements to a/v playback
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- [X] `./mach test-tidy` does not report any errors
This PR implements a backoff protocol to keep us from dropping frames whenever it's possible. It also add some other improvements like:
- Clean up the implementation a little bit by adding all fetch request related state to `HTMLMediaElementFetchContext`.
- Make sure that we ignore responses from old requests.
- Set the stream to seekable iff there's support for range requests. This will likely change when we add the media cache.
- Implements part of [step 8 of the seek spec](https://html.spec.whatwg.org/multipage/media.html#dom-media-seek) where we bail out if the stream is not seekable.
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