Add lots of Arc’s in style, and prepare for using DOMRefCell
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`DOMRefCell` usage is not there year because of thread-safety questions, but I have this much already that I’d like to land before it bitrots.
r? @emilio
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- [ ] These changes fix #__ (github issue number if applicable).
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- [x] These changes do not require new tests because refactor
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Convert imports in generate_imports into one per line, so that it can…
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Convert imports in generate_imports into one per line, so that it can easily add new ones with alphabetical order.
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- [X] These changes fix#13036 (github issue number if applicable).
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… easily add new ones with alphabetical order.
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Fix ridiculous DOM proxy getter performance
This implements the missing shadowing checks that were causing us to take many slow paths when dealing with proxy objects. Verified by running `tests/html/binding_perf.html` before and after and observing a 12x improvement.
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#12357
- [X] These changes do not require tests because we can't test performance yet.
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Support pair and value iterable WebIDL bindings
The actual iterator implementation and JSAPI calls related to setting up the interface are ported directly from Gecko's Codegen.py, IterableIterator.h, and IterableIterator.webidl. The changes to support multiple interfaces in one file are required because the internal iterator interface the parser generates gets associated with the original interface's WebIDL file. It seemed like a good time to address #571 in that case.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#12628 and fix#571.
- [X] There are tests for these changes
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