Fix ServiceWorker in multiprocess
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FIX#15217FIX#26100
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There is no need to set the dirty descendants flag unsafely from the layout side
for elements with pending restyles, we can do that on the DOM side when draining
the restyles from the Document.
More layout cleanups from the introduction of a lifetime in LayoutDom<T>
What can I say, the follow-up fixes just kept coming to my door one by one, I couldn't just tell them to go away.
For clarity, I introduce <LayoutDom<Element>>::parent_node_ref to contain
the remaining unsafety bits out of composed_parent_node_ref which is more
complex than just a field access.
webgl: Don't dirty canvas element while in immersive mode.
There are various WebGL APIs that are supposed to trigger a frame composite at the end of the event loop when they're used. We enforce this via dirtying the canvas element and ensuring that reflow occurs for normal content. This is redundant when we're using immersive mode and incurs extra work by the layout thread and compositor that inhibits the immersive rendering performance.
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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 (part of) #26019
- [x] These changes do not require tests because we do not have infrastructure to test immersive mode on CI.
They don't do anything fancy so there is no additional unsafety calling them
compared to using LayoutDom in the first place, the usual story of all
those changes.
This safe method is the basic block to access element attributes from layout.
We reuse it in the other attr-related layout methods to remove a pretty big
source of rampant unsafe code between script and layout.
Make LayoutNodeHelpers::text_content return a cow
What does it mean? It means that layout can process `Text` nodes' contents by just borrowing them, potentially saving us from a lot of unnecessary tempoorary allocations, which is nice.
Fix tojson unconditionally serializes
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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#25281
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