Improve worker shutdown
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FIX#26548FIX#25212
and also a step towards https://github.com/servo/servo/issues/26502
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Remove unnecessary generics from low-level script code
This should remove one of the larger offenders from the cargo-llvm-lines output for the script crate.
Improve precision of sequence types for WebIDL codegen.
Unlike #26699, this doesn't attempt to improve any of the resulting types and only maintains the status quo.
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This is preparation for sharing this code with layout_2020 and
implementing selective off-the-main-thread animations.
We still look for nodes not in the flow tree in the layout thread.
Add FromJSValConvertible for enums
Fixes https://github.com/servo/servo/issues/26169
This adds FromJSValConvertible implementations for webidl enums, which allows them to be used within `sequence<>`, etc.
This also uses these implementations when converting arguments.
https://heycam.github.io/webidl/#es-overloads
In step 12, the platform object check is for substep 4, but importantly it only matters if `V` implements the matching interface. If not, it should be able to fall back to substep 10 and attempt conversion to a dictionary.
Fix tojson unconditionally serializes
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- [x] These changes fix#25281
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