Add support for more array-like types in is_array_like
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Fix panic when running test-background-fetch-permission.html
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* Propagate `Error::JSFailed` in `Permissions::create_descriptor`
* In `Error::to_jsval`, only check if a JS exception is not pending if `self` is not `Error::JSFailed`
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- [x] These changes fix#23645 (GitHub issue number if applicable)
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Remove unused code (3/N)
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Third PR in a series of PRs to remove unused/dead code from servo, powered by an (upcoming) tool of mine. Please take a look and tell me if you want to keep something.
* First PR: #23477
* Second PR: #23498
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- [ ] These changes fix #___ (GitHub issue number if applicable)
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Receive streams in WebRTC (and MediaStreamTrack support)
This adds the `ontrack` event handler to webrtc, and all the `MediaStreamTrack` stuff necessary to make it work.
WebRTC has the ability to group media tracks into streams using MSIDs, but I haven't yet figured out how to do this. For now, `ontrack` should work.
This _should_ be complete, but it hasn't yet been tested (hence the WIP)
r? @ferjm or @jdm
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MediaStream playback through audio and video elements
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