May need an exception for open generics

[jonstodle]

If the formatter tries to break an open generics definition over multiple lines, it ends up looking a bit silly with a line of only comma(s).

// This input
public class ClassName
{
    public void JustAMethod()
    {
        if (true)
        {
            var genericType = typeof(AnExceptionallyLongAndElaborateClassNameToMakeAnExampleRegardingOpenGenerics<,>)
                .MakeGenericType(typeof(string), typeof(int));
        }
    }
}

// Produces this output
public class ClassName
{
    public void JustAMethod()
    {
        if (true)
        {
            var genericType =
                typeof(AnExceptionallyLongAndElaborateClassNameToMakeAnExampleRegardingOpenGenerics<
                    ,
                >).MakeGenericType(typeof(string), typeof(int));
        }
    }
}