Checks that mutating private method wrapper does not crash descriptionForPrivateMethod
Found [[PrivateMethods]]: true
Method wrapper found: true
Mutating wrapper.value to non-function...
Re-inspecting private methods list:
{
    id : <messageId>
    result : {
        result : [
            [0] : {
                configurable : true
                enumerable : true
                isOwn : true
                name : 0
                value : {
                    className : Object
                    description : 
                    objectId : <objectId>
                    subtype : internal#privateMethod
                    type : object
                }
                writable : true
            }
        ]
    }
}
