docs: responseHeaders should be Record<string, string[]>

[miniak]

Description of Change

The values in responseHeaders are received as arrays as can be seen by running this code:

session.defaultSession.webRequest.onHeadersReceived((details, callback) => {
  console.log('onHeadersReceived', details)
  callback({ responseHeaders: details.responseHeaders });
})

session.defaultSession.webRequest.onResponseStarted((details) => {
  console.log('onResponseStarted', details)    
})

session.defaultSession.webRequest.onCompleted((details) => {
  console.log('onCompleted', details)    
})

outputs

onHeadersReceived {
  id: 1,
  url: 'https://www.example.com/',
  method: 'GET',
  timestamp: 1578667512665.565,
  resourceType: 'mainFrame',
  fromCache: false,
  statusLine: 'HTTP/1.1 200',
  statusCode: 200,
  responseHeaders: {
    'accept-ranges': [ 'bytes' ],
    'cache-control': [ 'max-age=604800' ],
    'content-encoding': [ 'gzip' ],
    'content-length': [ '648' ],
    'content-type': [ 'text/html; charset=UTF-8' ],
    date: [ 'Fri, 10 Jan 2020 14:34:06 GMT' ],
    etag: [ '"3147526947"' ],
    expires: [ 'Fri, 17 Jan 2020 14:34:06 GMT' ],
    'last-modified': [ 'Thu, 17 Oct 2019 07:18:26 GMT' ],
    server: [ 'ECS (bsa/EB20)' ],
    status: [ '200' ],
    vary: [ 'Accept-Encoding' ],
    'x-cache': [ 'HIT' ]
  },
  webContentsId: 1,
  referrer: ''
}

onResponseStarted {
  id: 1,
  url: 'https://www.example.com/',
  method: 'GET',
  timestamp: 1578667512682.504,
  resourceType: 'mainFrame',
  ip: '2606:2800:220:1:248:1893:25c8:1946',
  fromCache: true,
  statusLine: 'HTTP/1.1 200',
  statusCode: 200,
  responseHeaders: {
    'accept-ranges': [ 'bytes' ],
    'cache-control': [ 'max-age=604800' ],
    'content-encoding': [ 'gzip' ],
    'content-length': [ '648' ],
    'content-type': [ 'text/html; charset=UTF-8' ],
    date: [ 'Fri, 10 Jan 2020 14:34:06 GMT' ],
    etag: [ '"3147526947"' ],
    expires: [ 'Fri, 17 Jan 2020 14:34:06 GMT' ],
    'last-modified': [ 'Thu, 17 Oct 2019 07:18:26 GMT' ],
    server: [ 'ECS (bsa/EB20)' ],
    status: [ '200' ],
    vary: [ 'Accept-Encoding' ],
    'x-cache': [ 'HIT' ]
  },
  webContentsId: 1,
  referrer: ''
}

onCompleted {
  id: 1,
  url: 'https://www.example.com/',
  method: 'GET',
  timestamp: 1578667512683.189,
  resourceType: 'mainFrame',
  ip: '2606:2800:220:1:248:1893:25c8:1946',
  fromCache: true,
  statusLine: 'HTTP/1.1 200',
  statusCode: 200,
  responseHeaders: {
    'accept-ranges': [ 'bytes' ],
    'cache-control': [ 'max-age=604800' ],
    'content-encoding': [ 'gzip' ],
    'content-length': [ '648' ],
    'content-type': [ 'text/html; charset=UTF-8' ],
    date: [ 'Fri, 10 Jan 2020 14:34:06 GMT' ],
    etag: [ '"3147526947"' ],
    expires: [ 'Fri, 17 Jan 2020 14:34:06 GMT' ],
    'last-modified': [ 'Thu, 17 Oct 2019 07:18:26 GMT' ],
    server: [ 'ECS (bsa/EB20)' ],
    status: [ '200' ],
    vary: [ 'Accept-Encoding' ],
    'x-cache': [ 'HIT' ]
  },
  webContentsId: 1,
  referrer: '',
  error: 'net::OK'
}

Follow-up to #18302

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• 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: Fixed responseHeaders types in electron.d.ts

[release-clerk]

Release Notes Persisted

Fixed responseHeaders types in electron.d.ts

[trop]

I have automatically backported this PR to "7-1-x", please check out #21742

[trop]

I have automatically backported this PR to "8-x-y", please check out #21743