Add WebGL conformance 2.0.0 tests
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This PR includes WebGL conformance 2.0.0 tests. For now I have disabled three folders in the new suite:
- `Conformance`: Tests WebGL 1.0 API like the current 1.0.3 suite we are using, but it includes a lot more tests and many expectations have to be updated. This is better to do in a separate PR because it will require to update github intermittent paths again and maybe detect new intermittents.
- `Conformance2\textures`: It causes a lot of timeouts because of using videos, svgs, and other complicated formats.
- `deqp`: It's a extra GPU testing suite included in the Khronos 2.0.0 suite. Disabled for now because it causes some timeouts.
So in a nutshell, it uses part of the 2.0.0 suite to test webgl 2.0 and keeps using 1.0.3 in order to test WebGL 1.0. It's good enough to enable TDD for the new WebGL 2.0 features
We can create follow-up issues for the next steps:
* deprecate 1.0.3 and use the new 'conformance' folder in 2.0.0 in order to test WebGL 1.0
* Enable `conformance2/textures` and 'deqp' tests once WebGL 2.0 implementation is more advanced or the timeouts are monitored in more detail.
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This enables it to be compiled without libservo:
```
cargo build --manifest-path components/script/Cargo.toml
```
… and then to be added to http://perf.rust-lang.org/
changed f64 to u64 for navigation start timing until it had to be float
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Fixes#19063
This PR renames the unused variables mentioned in issue #19063.
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Add support for filtering WebGL extensions based on WebGL version
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Add support for filtering WebGL extensions based on WebGL version
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Constified enums are default now. I think I want to introduce an option to
bindgen to allow setting the default enum behavior, but it doesn't need to block
this.
The ServoBindings.toml changes are somewhat hacky, but that's because of
https://github.com/rust-lang-nursery/rust-bindgen/issues/1125.
Also, the fixups now need to account for whitespace, since quote generates stuff
like root :: nsString, and we don't rustfmt the bindings if there's no rustfmt
installed.
Bug: 1412486
Reviewed-by: xidorn
MozReview-Commit-ID: EY5eNnCiTIw
Bindgen doesn't know how to derive debug for a Gecko font family list. Hopefully
it doesn't need to.
Bug: 1412486
Reviewed-by: xidorn
MozReview-Commit-ID: 4iZKzjad6K9
The code that uses it is of dubious utility, fwiw, but some of it is used on
Servo, so I'll kill that separately.
Bug: 1412486
Reviewed-by: xidorn
MozReview-Commit-ID: KauvXX32zLM
