Removed integrity check and test for no-cors requests
Removed Step 30.2 which raised a JS TypeError if the integrity metadata was not empty. I manually ran `new Request("", {"mode" : "no-cors", "integrity" : "not an empty string"});` in servo to validate that the exception no longer arose.
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- [x] These changes fix#18345
- [x] These changes do not require tests because according to the ticket "Unfortunately, there's no automated test available for this yet because we are having trouble updating our copy of the upstream tests. "
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Mark dictionaries containing GC values as must_root, and wrap them in
RootedTraceableBox in automatically-generated APIs. To accommodate
union variants that are now flagged as unsafe, add RootedTraceableBox
to union variants that need to be rooted, rather than wrapping the
entire union value.
A media element can delay the document's load event without having a resource URL,
and it can even block it while being inserted into a different document AFAIK.
Remove sources of panic when laying out an iframe without a nested browsing context
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At the moment, layout panics if it discovers an iframe without a nested browsing context. Under normal circumstances, this is reasonable, but it requires very tight synchronization between script, layout, the constellation and the compositor. In particular, if a layout is in progress when an iframe's browsing context is discarded, this can trigger panic.
This PR fixes this in two ways:
1. Making the pipeline and browsing context ids optional in layout's representation of an iframe.
2. Shutting down layout before discarding a browsing context, rather than after.
This is belt and braces.
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- [X] These changes fix#17482 and #18477
- [X] These changes do not require tests because the PR is fixing a panic caused by a race condition
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Using OnceCell<T> from Mitochondria
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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#13402 (github issue number if applicable).
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