It could be used to have mutable JSVal fields without GC barriers.
With the removal of that trait, MutHeap and MutNullableHeap can respectively
be replaced by MutJS and MutNullableJS.
Support SVG element
<!-- Please describe your changes on the following line: -->
minimal SVG element implementation
---
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#12974 (github issue number if applicable).
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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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This commit adds new files related to implementing the [Request
API](https://fetch.spec.whatwg.org/#request-class). This commit also
changes the expected web platform tests results. It also modifies the
following files:
components/net_traits/request.rs
HeapSizeOf is implemented in net_traits/request so that dom::request can
be used as a wrapper around net_traits::request::Request.
components/script/dom/headers.rs
Several methods are added to Headers so that request can access and
modify some of the headers fields.
This commit introduces the `WebGLValidator` trait, and uses it for multiple
validations in the texture-related WebGL code, to move that logic out of the
already bloated `webglrenderingcontext.rs` file.
It also creates a type-safe wrapper for some WebGL types, removing all the
`unreachable!`s there, and introduces a macro for generating them conveniently.
This partially addresses #10693, pending refactor more code to use this
infrastructure, and (possibly?) introducing an `AsGLError` trait for the errors
to make the error handling happen in `WebGLContext`.
