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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This avoids grabbing the document when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
This avoids grabbing the document when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
It logically belongs there, and the only reason it wasn't there before we were
working around it.
MozReview-Commit-ID: 5a5iksHAIdN
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
Use whether we've computed any viewport unit instead.
This is more accurate (we avoid restyling unnecessarily if we've found anything
ever on the stylesheet, but that hasn't matched).
This has the benefit of also matching Gecko, and simplify some code and
fishyness around, and also hopefully speeding up stylesheet parsing.
style: Move the StyleSheetSet into the Stylist.
This will allow tracking whether there have been only additions to the
stylesheet set, and in that case don't destroy and completely rebuild the
invalidation map.
This is on top of #18143.
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This will allow tracking whether there have been only additions to the
stylesheet set, and in that case don't destroy and completely rebuild the
invalidation map.
The only reason why we had the `existing_style_for_style_damage` bit is to apply
some optimizations that we don't have anymore.
I still want to reintroduce a few of them, at least for the non-eager
pseudo-element case... But I think I won't need this at all.
This allows us to remove a fair amount of Gecko code too.
End TreeBuilder's reliance on DOM.
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Fixed h5e's TreeBuilder so that it does not use `same_tree` and `has_parent_node` methods: d8c2ea5cb6
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This is a patch that unifies a bit how Gecko and Stylo stylesheets work, in
order to be able to eventually move the stylesheets into the stylist, and be
able to incrementally update the invalidation map.
Deduplicating code is nice, and it will help us when we make the bit
propagation more complicated in upcoming patches.
MozReview-Commit-ID: KIQnNJVayrM
WR multi-document update
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The PR updates WR version to support multiple documents (https://github.com/servo/webrender/pull/1509) but doesn't take advantage of this new feature yet.
It also makes Servo to use `DevicePixel` from WR instead of rolling out another one.
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- [ ] These changes fix #__ (github issue number if applicable).
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