e775b49e95
Motivation: PromiseAggregator's API allows for the aggregate promise to complete before the user is done adding promises. In order to support this use case the API structure would need to change in a breaking manner. Modifications: - Deprecate PromiseAggregator and subclasses - Introduce PromiseCombiner which corrects these issues Result: PromiseCombiner corrects the deficiencies in PromiseAggregator.