it's a good opportunity to refactor a bit this callback because both alternatives does almost the same thing so the whole method could be written like:
```js
    ContentService.prototype.createContentDraft = function createContentDraft(contentId, versionId, callback) {
        var that = this;

        this.loadContentInfo(
            contentId,
            function (error, contentResponse) {
                var url = '';

                if (!error) {
                    if (typeof versionId !== "function") {
                        url = contentResponse.document.Content.Versions._href + "/" + versionId;
                    } else {
                        callback = versionId;
                        url = contentResponse.document.Content.CurrentVersion._href;
                    }

                    that._connectionManager.request(
                        "COPY", url, "",
                        { "Accept" : "application/vnd.ez.api.Version+json" },
                        callback
                    );
                } else {
                    callback(error, false);
                }
            }
        );
    };
```