Add a sampling profiler
This uses the code already built for the background hang monitor and adds the ability to repeatedly sample all monitored threads. This sampling allows us to generate profiles that we can translate into the format used by https://perf-html.io/, allowing us to benefit from modern Gecko performance tooling.
You can run Servo with `PROFILE_OUTPUT=foo.json` and `SAMPLING_RATE=50` (for example), otherwise these values will default to `samples.json` and 10ms, respectively. To activate the profiler, press cmd+p, and to stop profiling, press cmd+p again. This will the captured samples to be symbolicated, which will take a very long time, and eventually there will be a new JSON profile in the output location.
To create a profile for use by Gecko's tools, run `python etc/profilicate.py path/to/profile.json >gecko_profile.json`, and load `gecko_profile.json` in the https://perf-html.io/ to see something like [this](https://profiler.firefox.com/public/8137e2b11fbb92afb80090bc534fd83015c87ee6/calltree/?globalTrackOrder=0-1&thread=1&v=3);
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- [x] `./mach build -d` does not report any errors
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- [x] These changes fix#13103
- [x] These changes do not require tests because way too many pieces to automate
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Have embedders send DOM keys to servo and use a strongly typed KeyboardEvent
from the W3C UI Events spec. All keyboard handling now uses the new types.
Introduce a ShortcutMatcher to recognize key bindings. Shortcuts are now
recognized in a uniform way.
Updated the winit port.
Updated webdriver integration.
part of #20331
Use typed coordinates more
Requires https://github.com/servo/servo/pull/19895
We use Size2D and Point2D across compositing, constellation and script, loosing the type of pixels we use (DevicePixel, DeviceIndepententPixel or CSSPixel) along the way, which might lead to bugs like `window.outerHeight` not taking into account the page zoom (using DeviceIndepententPixel instead of CSSPixel).
This should make the situation a bit better.
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We use Size2D and Point2D across compositing, constellation and script,
losing the type of pixels we use (DevicePixel, DeviceIndepententPixel
or CSSPixel) along the way, which might lead to bugs like
window.outerHeight not taking into account the page zoom (using
DeviceIndepententPixel instead of CSSPixel).
Make it possible to close a browsing context from the embedder
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- [x] These changes fix#18006 (github issue number if applicable).
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remove no-op InitializeCompositing message
I think this is no-op.
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This patch fixes a couple of issues in the compositor:
1) Remove the delayed composition code. Previously, this would schedule
a composite for 12ms in the future. This doesn't really make any sense
with WR. There's no point in doing a composite unless WR has provided
a new frame to be drawn. This fixes issues in several benchmarks where
we were doing multiple composite / renders per rAF, which is a waste
of CPU time. This *does* make the framerate slower in some cases (such
as a slow rAF callback) but it's more correct - otherwise we were just
compositing the same frame multiple times for no real benefit.
2) Inform the window of the current animation state of the compositor.
Specifically, if an animation (or rAF) is currently active, the
window system switches to use event polling, and does not block on
the OS-level event loop. In the case of active animation, we just
assume that we want to be running as the vsync interval and not
blocking. This means the compositor thread only sleeps on vsync
during animation, which reduces OS scheduling and results in much
smoother animation.
