FILE: mutableList.kt
    public final fun foo(): R|kotlin/Unit| {
        lvar listVar: R|kotlin/collections/MutableList<kotlin/Int>| = R|kotlin/collections/mutableListOf|<R|kotlin/Int|>(vararg(Int(1), Int(2), Int(3)))
        R|<local>/listVar| = R|<local>/listVar|.<CS errors: kotlin/collections/plus>#<R|kotlin/Int|>(Int(4))
    }
