Flow didn't catch a call to missing property(or method) on a function

[AVykhrystyuk]

Flow version: 0.100.0

// @flow strict

function func(): void {
  return func.somethingMissing(); // <-- property 'somethingMissing' is missing
}

function func2(): number {
  return func2.__length__; // <-- property '__length__' is missing
}

Expected behavior

Flow yields an error that property 'x' is missing on a function

Actual behavior

Flow didn't catch a typo, so if that code is not covered by tests - you get a runtime error.

• Link to Try-Flow or Github repo: https://flow.org/try/#0PTAEAEDMBsHsHdQGcAuAnAlgYxQKF5AK4B2OGsxoRpAFAJQBcoAbrBgCagDeuooaAUxSE0lalgB0SWAFshACwzEA5gFkMSJEuX0A3KBCgAPAFoToAA5pYFgWhQBPUAHJpclIpXrN256A2gMhpaKrgAvvjiKORiJFgATPRMxIQyAEZ23Lz8QiKxpPESAPpF0AIqHiX6hqbmVjZ2ji4lZRXyJX4BQT6hEUA

• Link to how the same is handled in Typescript:
  https://www.typescriptlang.org/play/index.html#src=function%20func()%3A%20void%20%7B%0A%20%20return%20func.somethingMissing()%3B%20%2F%2F%20%3C--%20property%20'somethingMissing'%20is%20missing%0A%7D%0A%0Afunction%20func2()%3A%20number%20%7B%0A%20%20return%20func2.__length__%3B%20%2F%2F%20%3C--%20property%20'__length__'%20is%20missing%0A%7D%0A

[goodmind]

Duplicate of #106