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.
Update `trace-dump.{js,css}` from upstream
Part of making the trace-dump.js code unit testable was moving it out to another
repo. This brings in all the changes made while writing unit tests, and making
the code more unit testable.
Unfortunately, there are a lot of whitespace changes; here is the diff ignoring whitespace: https://pastebin.mozilla.org/8870346Fixes#10905.
r? @jdm
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Part of making the trace-dump.js code unit testable was moving it out to another
repo. This brings in all the changes made while writing unit tests, and making
the code more unit testable.
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.
* Sections like `[dependencies.foo]` can be entries in a `[dependencies]`
section with the `{key = value}` syntax.
* Per-target dependencies can be expressed with more general `cfg(…)`
conditions instead of exact target triples:
https://github.com/rust-lang/cargo/pull/2328
Added #[allow(unused_extern_crates)] to silence false positives
* bitflags, lazy_static and matches because macro_use
* alloc_jemalloc because builtin crate
See https://github.com/rust-lang/rust/issues/30849
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.
Instead of producing a tree of stacking contexts, display list
generation now produces a flat list of display items and a tree of
stacking contexts. This will eventually allow display list construction
to produce and modify WebRender vertex buffers directly, removing the
overhead of display list conversion. This change also moves
layerization of the display list to the paint thread, since it isn't
currently useful for WebRender.
To accomplish this, display list generation now takes three passes of
the flow tree:
1. Calculation of absolute positions.
2. Collection of a tree of stacking contexts.
3. Creation of a list of display items.
After collection of display items, they are sorted based upon the index
of their parent stacking contexts and their position in CSS 2.1
Appendeix E stacking order.
This is a big change, but it actually simplifies display list generation.
