Bug 1650464

Cause: Resources loaded through the ConnectToState component (in firehose.jsx) were considered collectively loaded if the loaded state of all required resources was true. Optional resources' loaded state was not being checked. This means that the loaded prop set by this component could be true before optional resources were finished loading. Consequence: When optional resources are passed to FIrehose, and no required resources exist, an empty state might be displayed momentarily before optional resources have a chance to finish loading. Fix: The logic for setting the 'loaded' prop created in ConnectToState is now as follows: - Optional resources are considered loaded if and only if either their loaded state is true or their loadError state is not empty. - Required resources are considered loaded if and only if their loaded state is true - If all optional and required resources are considered loaded by the above logic, the loaded prop will be true. Result: An empty state is no longer displayed before optional components are finished loading.