Support Asyncify for Blazor scenarios

[AaronRobinsonMSFT]

Asyncify permits making an existing synchronous API utilize a JavaScript/WASM asynchronous based API.

An example of the Julia runtime adding support - JuliaLang/julia#32532.

See #37669

/cc @steveisok @lewing @marek-safar

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Issue Details

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Asyncify permits making an existing synchronous API utilize a JavaScript/WASM asynchronous based API.

An example of the Julia runtime adding support - JuliaLang/julia#32532.

See #37669

/cc @steveisok @lewing @marek-safar

Author:	AaronRobinsonMSFT
Assignees:	-
Labels:	arch-wasm, area-Codegen-LLVM-mono, untriaged
Milestone:	-

[lewing]

For background https://kripken.github.io/blog/wasm/2019/07/16/asyncify.html covers the benefits and limitations. The limitations there are hard to avoid in the current runtime but we should expand on the reasoning here.

[lewing]

The limitations around this approach in the browser scenario make it unsuitable for a general sync over Promise solution.