query.areAllParametersSet does not work with observable parameters

[bnordli]

If a query has observable parameters, areAllParametersSet will return true even when this observable parameter has null value.

Example:

query = someQuery.create();
query.someParameter(ko.observable());
query.areAllParametersSet(); // will return true.

[bnordli]

Note: This leads to potentially running the query with a null or undefined parameter, resulting in a NullReferenceException in QueryService.PopulateProperties.