How to handle functions that return a promise

[mmuffins]

Hi everybody,
I'm trying to retrieve data from a javascript function in an application running on Chromium v53. The function returns a promise which contains an object with the values I'm looking for. The problem I'm having is that I can't resolve the promise.
The following code works fine if I execute it directly in chrome:

var list = app.db.getTracklist('SELECT * FROM Songs', -1);
console.log(list.isLoaded); // returns false
console.log(list.asJSON); // returns blank data

list.whenLoaded().then(function(result){
	console.log(result.isLoaded) //returns true
	console.log(result.asJSON) // returns the data I want
})

What I want to do in my application is the following:

var cmd = new EvaluateCommand{
	ObjectGroup = "console",
	IncludeCommandLineAPI = true,
	DoNotPauseOnExceptionsAndMuteConsole = false,
	ReturnByValue = true,
	Expression = "app.db.getTracklist('SELECT * FROM Songs', -1)"
};

var response = chromeSession.SendAsync(cmd).Result as CommandResponse<EvaluateCommandResponse>;

Console.WriteLine(response.Result.Result.Value);

The last line prints a json object which has the properties isLoaded and asJSON - which are false and blank, respectively. That makes sense since whenLoaded() needs to be called in order to load the data. If I change the expression of the call to "app.db.getTracklist('SELECT * FROM Songs', -1).whenLoaded()", SendAsync() returns a promise (as opposed to the object the promise returns). If I execute synchronous functions I get correct results, so I'm positive that the basic setup is fine.

Does anybody know what I need to do in order to get the data that would be returned in the then() block of the original function?