fix#18594: Unnecessarily allocating an error string
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r? @asajeffrey
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style: Make sure to not run any style invalidation in an unstyled children only traversal.
Bug: 1402472
Reviewed-by: bholley
MozReview-Commit-ID: IFPA7LJpvsZ
Remove unused 'untagged_unions' feature gate
CC #5286
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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 do not require tests because the PR is fixing a panic caused by a race condition
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Make tidy aware of Rust multiline strings
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This makes the internal tidy script properly ignore the contents of Rust multiline strings.
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As a result of tighter and more correct handling of character
literals, this now catches a few kinds of syntax involving lifetimes
that were previously missed, so those have been updated.
`AnimationValue` has its own path for conversion to computed values, so we need
to update `for_non_inherited_property` in the context to match the property
being converted.
I didn't notice any other generic conversions, so hopefully this is the only
missing path.
MozReview-Commit-ID: HskrpMctmYE
Remove unused feature gates
CC #5286.
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Using OnceCell<T> from Mitochondria
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- [x] These changes fix#13402 (github issue number if applicable).
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