[v10.x] process: split bootstrappers by threads that can run them

[joyeecheung]

This patch split part of the bootstrappers into three files:

• lib/internal/process/main_thread_only.js: contains bootstrappers
  that can only be run in the main thread, including
  • setupStdio for the main thread that sets up process.stdin,
    process.stdout, process.error that may interact with external
    resources, e.g. TTY/File/Pipe/TCP sockets
  • setupProcessMethods that setup methods changing process-global
    states, e.g. process.chdir, process.umask, process.setuid
  • setupSignalHandlers
  • setupChildProcessIpcChannel that setup process.send for
    child processes.
• lib/internal/process/worker_thread_only.js: contains bootstrappers
  that can only be run in the worker threads, including
  • setupStdio for the worker thread that are streams to be
    manipulated or piped to the parent thread
• lib/internal/process/per_thread.js: contains bootstrappers
  that can be run in all threads, including:
  • setupAssert for process.assert
  • setupCpuUsage for process.cpuUsage
  • setupHrtime for process.hrtime and process.hrtime.bigint
  • setupMemoryUsage for process.memoryUsage
  • setupConfig for process.config
  • setupKillAndExit for process.kill and process.exit
  • setupRawDebug for process._rawDebug
  • setupUncaughtExceptionCapture for
    process.setUncaughtExceptionCaptureCallback and
    process.hasUncaughtExceptionCaptureCallback

Hopefully in the future we can sort more bootstrappers in
boostrap/node.js into these three files and further group
them into functions that can be run before creating the
snapshot / after loading the snapshot.

This patch also moves most of the isMainThread conditionals
into the main bootstrapper instead of letting them scattered around
special-casing different implementations.

PR-URL: #21378
Reviewed-By: Gus Caplan me@gus.host
Reviewed-By: Anna Henningsen anna@addaleax.net
Reviewed-By: Jeremiah Senkpiel fishrock123@rocketmail.com

[nodejs-github-bot]

@joyeecheung build started: https://ci.nodejs.org/blue/organizations/jenkins/node-test-pull-request-lite-pipeline/detail/node-test-pull-request-lite-pipeline/301/pipeline

[joyeecheung]

cc @targos

[targos]

Thanks!

[targos]

Full CI: https://ci.nodejs.org/job/node-test-pull-request/15924/

[targos]

Landed in 581390c