Formatter doesn't increase ident in multiline list patterns correctly

Found while working on a compiler PR (link)

Version Used: VS 17.10.0 Preview 5.0

Steps to Reproduce: Run formatter on this code:

MyClass[] arr = [new()];

if (arr is
    [
    {
        Prop: 1,
        AnotherProp: 2
    }
    ])
{

}

class MyClass
{
    public int Prop { get; set; }

    public int AnotherProp { get; set; }
}

Expected Behavior:

MyClass[] arr = [new()];

if (arr is
    [
        {
            Prop: 1,
            AnotherProp: 2
        }
    ])
{

}

class MyClass
{
    public int Prop { get; set; }

    public int AnotherProp { get; set; }
}

Actual Behavior: Quite the opposite - when I run formatting on correct code, it dedents it back: