http2: backport changes to v9.x-staging

[jasnell]

Backport of multiple http2 related commits to v9.x-staging.

Currently blocked by #18049 and whatever else is currently causing v9.x-staging to fail. Will be able to finish once v9.x-staging is functioning again.

Note: have not fully tested this yet because of the v9.x-staging breakage.

Ping @nodejs/http2 @mcollina

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Affected core subsystem(s)

http2

[targos]

v9.x-staging fails because #17704 is not in it. Is it possible to include it in this PR?

[jasnell]

Not sure. That's a semver-major pr so would need a semver-major minor backport that omitted the breaking bits. That would best be done in a separate PR.

[mcollina]

Could this commit be further backported to 8 in case?

[jasnell]

That's going to require a bit more work. Planning to do it later this week

[MylesBorins]

I've rebased against the new v9.x-staging to remove a commit that was breaking the build, it looks like another commit may be breaking stuff so i'll likely rebase one more time 😄

[targos]

@MylesBorins you are looking for #17800 which depends on #17704