Remove use of on_unimplemented
It errors in today’s Nightly:
```rust
error[E0557]: feature has been removed
--> components/script/lib.rs:9:12
|
9 | #![feature(on_unimplemented)]
| ^^^^^^^^^^^^^^^^ feature has been removed
error[E0658]: this is an internal attribute that will never be stable
--> components/script/dom/bindings/conversions.rs:77:1
|
77 | #[rustc_on_unimplemented(message = "The IDL interface `{Self}` is not derived from `{T}`.")]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: for more information, see https://github.com/rust-lang/rust/issues/29642
= help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
error: aborting due to 2 previous errors
```
This patch adds initial support for WebGLSync.
Note:
There is no test for the isSync, deleteSync and waitSync functions in the `conformance2/sync/sync-webgl-specific.html`.
There are a few canvas2d-related dependencies that haven't updated, but they
only use euclid internally so that's not blocking landing the rest of the
changes.
Given the size of this patch, I think it's useful to get this landed as-is.
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
---
- [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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