Add nullcheck generates poor formatting

[JohanLarsson]

Before:

        protected override void StopListening(object source)
        {
            ((ICommand)source).CanExecuteChanged -= this.DeliverEvent;
        }

After:

        protected override void StopListening(object source)
        {
            if (source == null)
            {
                throw new ArgumentNullException(nameof(source));
            } ((ICommand)source).CanExecuteChanged -= this.DeliverEvent;
        }

[JohanLarsson]

Too weird for today, failing tests:

            [Test]
            public static void WhenCastAndUnsubscribed()
            {
                var before = @"
namespace N
{
    using System;
    using System.ComponentModel;

    public class C
    {
        protected void M(object ↓source)
        {
            ((INotifyPropertyChanged)source).PropertyChanged -= this.M;
        }

        private void M(object sender, PropertyChangedEventArgs e)
        {
        }
    }
}";

                var after = @"
namespace N
{
    using System;
    using System.ComponentModel;

    public class C
    {
        protected void M(object source)
        {
            if (source is null)
            {
                throw new ArgumentNullException(nameof(source));
            }

            ((INotifyPropertyChanged)source).PropertyChanged -= this.M;
        }

        private void M(object sender, PropertyChangedEventArgs e)
        {
        }
    }
}";
                RoslynAssert.CodeFix(Analyzer, Fix, ExpectedDiagnostic, before, after);
            }

            [Test]
            public static void WhenCastAndInvoked()
            {
                var before = @"
namespace N
{
    using System;
    using System.ComponentModel;

    public class C
    {
        protected void M(object ↓source)
        {
            ((string)source).ToString();
        }
    }
}";

                var after = @"
namespace N
{
    using System;
    using System.ComponentModel;

    public class C
    {
        protected void M(object source)
        {
            if (source is null)
            {
                throw new ArgumentNullException(nameof(source));
            }

            ((string)source).ToString();
        }
    }
}";
                RoslynAssert.CodeFix(Analyzer, Fix, ExpectedDiagnostic, before, after);
            }