Initial implementation of WebGLQueries
This patch adds initial support for WeGLQueries. Most related WebGL functions and objects ([1]) are implemented; what's still missing is:
- syncing the result of `getQueryParameter` with the event loop
- `EXT_disjoint_timer_query_webgl2` support
[1]: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.12
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cc @jdm @zakorgy
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Add initial support for WebGL compressed textures
This patch is an initial implementation of WebGL compressed texture support, it contains
- functions for registering and querying compressed texture extensions
- initial implementation of `CompressedTexImage2D` and `CompressedTexSubImage2D` and their parameter validation
- implementation of S3TC (DXT1, DXT3, DXT5) and ETC1 extensions as examples
What's still missing:
- some of the parameter validation steps are missing
- the pixel comparison tests fail for more complex cases (I'm probably missing something trivial at the GL calls)
Related: #10209 and #20594
cc @jdm @zakorgy
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] Related issues: #10209, #20594
- [x] There are tests for these changes
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This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/23226)
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