Clear canvas thread state on recreation.
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The canvas rendering context is cleared when it is recreated, but not the matching state in the canvas paint thread.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#17533
- [X] These changes do not require tests because the css-paint-api tests test for this already.
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Correct viewport test references
These references were using an incorrect value for the expected
container width. Now that WebRender is no longer clipping to stacking
context boundaries the rendered width is correct (100% of viewport
width = 240px).
Sometimes clippy gets outdated by months, and its current support setup
means that each Servo component need to opt into it by depending on
the plugins crate manually, and not all components do that.
switch to using webrender_traits::ImageData
update use of webrender_traits::StackingContext in layout
use webrender_traits::channel::msg_channel in webgl ipc
fix use of resource_override_path in components/servo/lib
This removes paint threads, rust-layers dependency, and changes
optional webrender types to be required.
The use_webrender option has been removed, however I've left
the "-w" command line option in place so that wpt
runner can continue to pass that. Once it's removed from there
we can also remove the -w option.
Once this stage is complete, it should be fine to change the
display list building code to generate webrender display
lists directly and avoid the conversion step.
