This implements system level DPI awareness for Windows. It has three
parts:
1. Add a application manifest which is copied alongside servo.exe during
build that declares our DPI awareness level. This is needed otherwise
DPI queries will return 96dpi and our application will be upscaled on
high DPI displays.
2. Rename hidpi_factor to avoid confusion with Glutin's hidpi_factor
which does something else.
3. Correctly convert windows sizes on window creation for
Windows. Unlike OS X, Windows uses device pixels for window creation.
This changes headless operation to strictly be a runtime option, rather
than a compile-time one. Note that the old headless version still relied
on a display server to support WebGL, while it now requires one all the
time.
Fixes#8573
has loaded.
This avoids a flash of unstyled content, which looks especially bad in
browser.html since unstyled content is white and browser.html has a
transparent background.
Closes#9996.
Update to latest rust-layers
The compositing context, painting context and display metadata have all
been collapsed into a single NativeDisplay class.
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This is important for the SERVO_HEADLESS configuration, because
creating a clipboard on linux creates an X context which then causes
reftest instability.
The basic idea is it's safe to output an image for reftest by testing:
- That the compositor doesn't have any animations active.
- That the compositor is not waiting on any outstanding paint messages to arrive.
- That the script tasks are "idle" and therefore won't cause reflow.
- This currently means page loaded, onload fired, reftest-wait not active, first reflow triggered.
- It could easily be expanded to handle pending timers etc.
- That the "epoch" that the layout tasks have last laid out after script went idle, is reflected by the compositor in all visible layers for that pipeline.
This used to conflict with the util crate from the standard library, which
has long since been removed.
The import in layout has not been changed because of a conflict with the
util mod there.
