feat: migrate protocol module to NetworkService (Part 4)

[zcbenz]

Description of Change

Refs #15791.

This is part of the changes to reimplement the protocol module with NetworkService API, the new implementation lives in parallel with current implementation and only gets used when --enable-features=NetworkService is passed.

This PR implements the protocol.registerStreamProtocol with NetworkService APIs, and also refactors the code of AtomURLLoaderFactory.

Due to the migration of NetworkService APIs, it is now possible to return different types of responses in one protocol handler, I have added an experimental protocol.registerProtocol API to demonstrate the possibility:

protocol.registerProtocol('test', (request, callback) => {
  if (/* stream */) {
    callback('stream', {
      statusCode: 200,
      headers: {
        'content-type': 'text/html'
      },
      data: createStream('<h5>Response</h5>')
    })
  } else if (/* file */) {
    callback('file', '/path/to/file')
  }
})

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• tests are changed or added
• relevant documentation is changed or added
• PR title follows semantic commit guidelines
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: no-notes

[deepak1556]

Is it okay for this class to manage its own lifetime ?

[zcbenz]

This seems to be the only choice, I couldn't find a way to have Chromium manage its lifetime. content::FileURLLoader is also managing its own lifetime:

https://cs.chromium.org/chromium/src/content/browser/file_url_loader_factory.cc?type=cs&g=0&l=341

[deepak1556]

Oh cool, in that case should we check if producer_ and client_ handles are bound before accessing the methods when we receive data from JS land ?

[zcbenz]

content::FileURLLoader does not check bound for every call but it deletes itself when connection error happens, I have added the same for NodeStreamLoader.

[release-clerk]

No Release Notes