WebGPU APIs return null instead of undefined

[andyleiserson]

In the WebGPU spec, many APIs return undefined. It seems that the object wrap maps () to null. This check in the WebGPU CTS is sensitive to the difference. Repro command (in wgpu repo): cargo xtask cts 'webgpu:api,validation,encoding,cmds,compute_pass:set_pipeline,*'.

The fix is simple enough, but needs to be made to a bunch of APIs. I'm also not sure if there is a simpler way to do it than in the branch I linked, or even if the javascript mapping of () should be changed.

Deno crate versions:

deno_console = "0.192.0"
deno_core = "0.338.0"
deno_url = "0.192.0"
deno_web = "0.224.0"
deno_webidl = "0.192.0"
deno_webgpu = { version = "0.157.0", path = "./deno_webgpu" }
deno_unsync = "0.4.2"
deno_error = "0.5.5"

[petamoriken]

Simply add #[undefined] in the same way as #29567.

[andyleiserson]

Sadly it's not that simple, the latest deno requires Rust 2024, which wgpu doesn't have yet due to Rust-GPU/rust-gpu#182. But I do have a branch that adds #[undefined] on the relevant APIs, for when it is useful.

[LegNeato]

rust-gpu is now on a later rust version and should no longer block, thanks!