Refactor `.sort_by()` calls to use `.partial_cmp()`
Changes the closures passed to `sort_by` in this file with a simpler, and more correct version.
Previously, potential NaNs in the array would float to the top. Either way, the program would crash, as the `get_statistics` function asserts the array it gets is sorted, which always fails with a NaN.
Because of that, this change should not affect functionality.
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WebRender.
This happens asynchronously, just as it does in non-WebRender mode.
This functionality is a prerequisite for doing proper display-list-based
hit testing in WebRender, since it moves the scroll offsets into Servo
(and, specifically, into the script thread, enabling iframe event
forwarding) instead of keeping them private to WebRender.
Requires servo/webrender_traits#55 and servo/webrender#277.
Partially addresses #11108.
This commit adds the `--profiler-trace-path` flag. When combined with `-p` to
enable profiling, it dumps a profile as a self-contained HTML file to the given
path. The profile visualizes the traced operations as a gant-chart style
timeline.
speculation code.
The old code tried to do the speculation as a single bottom-up pass
after intrinsic inline-size calculation, which was unable to handle
cases like this:
<div>
<div style="float: left">Foo</div>
</div>
<div>
<div style="overflow: hidden">Bar</div>
</div>
No single bottom-up pass could possibly handle this case, because the
inline-size of the float flowing out of the "Foo" block could never make
it down to the "Bar" block, where it is needed for speculation.
On the pages I tried, this regresses layout performance by 1%-2%.
I first noticed this breaking some pages, like the Google SERPs, several
months ago.
bottom-up pass.
Right now, the only reason that overflow calculation works is that we
rely on script inducing extra reflows that are sent for display. This
was preventing #10021 from landing.
This change regresses layout performance by about 1% in my tests.
Fixes#7797 properly.
