Condition doesn`t check undefined when direct import #17189

export let c:number|undefined

import {c} from './A'
import * as A from './A'

function foo(a:number) {
}

if (c) {
        foo(c) // B.ts(8,6): error TS2345: Argument of type 'number | undefined' is not assignable to parameter of type 'number'.  Type 'undefined' is not assignable to type 'number'.
}

if (A.c) {
	foo(A.c) // All right
}