Make canvas origin clean checks use origin of image response
Adapted from #15887.
---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#15409
- [X] There are tests for these changes
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Move bindings tests out of the style crate
This cuts in almost half the time to run:
```
touch components/style/lib.rs
./mach test-stylo
```
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Implement WebGL extensions
<!-- Please describe your changes on the following line: -->
This PR provides the base for implementing WebGL extensions. It comes with the following ones already implemented and passing all related WebGL conformance tests:
- OES_texture_float
- OES_texture_float_linear
- OES_texture_half_float
- OES_texture_half_float_linear
- OES_vertex_array_object
I'll submit other extensions like compressed textures in a separate PR to ease the review process. I included the 5 extensions in this PR because it's easier to show/review how the WebGL extension base works.
To pass all OES_texture_float_xxx tests I had to add some missing format conversions in WebGLRenderingContext.rs
---
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Allow -moz-stack-sizing to work in a single direction only.
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https://bugzilla.mozilla.org/show_bug.cgi?id=1364115https://reviewboard.mozilla.org/r/138434/
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Stylo: Add support for grid-template-{rows,columns}
This has the implementation of grid's `<track-list>` nightmare.
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- [x] These changes fix#15311
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Check snapshot id/class flags before looking for those attributes.
<!-- Please describe your changes on the following line: -->
Most elements don't have classes or IDs.
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- [X] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1365659
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