measure blocked layout queries
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No longer needed now that the case-sensitive flag for attributes selectors is
supported.
Update user-agent CSS sheet to use the standard flag.
Fixes#23227
Reduce unnecessary iframe size messages
This should be an improvement on pages that include iframes, since we currently run two layout jobs for every display-oriented layout request. When building the display list, we send a message to the constellation that includes the sizes of all iframes present, and the constellation sends resize messages to the script thread. This results in a mouse event on the outer page causing all frames to be re-laid out even if no changes occurred to the iframe sizes, which is ridiculous.
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- [x] These changes fix#22394
- [x] These changes do not require tests because there is no way to test this internal detail.
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Added comment about layout thread exit workflow
Comments
Regarding clarify layout-thread exit workflow (Specifically:when will a Exit message be received )
Added comment about layout thread exit workflow
Instead of per-document. This also allows to reuse this thread-pool if needed
for other stuff, like parallel CSS parsing (#22478), and to share more code with
Gecko, which is always nice.
Previously, the `tests` feature flag of the `embedder_traits` crate
caused it and every crate recursively depending on it to be built twice.
This feature flag was used to provide a specific set of "resources"
when running tests. Instead, this commits overrides the `main()` function
of the test harness to change resources at runtime before running any test.
This is done by adding a dependency that has `name = "test"` in its
`[lib]` section of `Cargo.toml`. This overrides the crate found by
`extern crate test;` in code generated by `rustc --test`.
Current pixel density
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- [x] These changes fix a subset of #11416.
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Rustfmt layout_thread crate
Part of #21373. Checked all changes looks good. 🎉 Manually removed two optional semicolons within unsafe so that it is formatted in one line.
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