Function init

test/async_hooks.test.js:10–14

(asyncId, type, triggerAsyncId, resource)

createHook({
  init (asyncId, type, triggerAsyncId, resource) {
    if (type === 'content-type-parser:run') {
      remainingIds.add(asyncId)
    }
  },
  destroy (asyncId) {
    remainingIds.delete(asyncId)
  }