The existing Web Service is not working as expected in some cases such as sequential navigation and when we need to retrieve the submission summary status (regardless the display options settings).

Required changes are:

1. Return the state id ignoring the correctness status
2. Return the number of unanswered questions so we can display the warning.
3. When sequential navigation is on, currently all questions are ignored and not returned by the WS except the current one. The implementation needs to consider that the user is able to know the number of total questions and previous question statuses. But it should not know future questions content.

Notes for integrators and reviewers:

• We are not backporting these changes as we are modifying the Web Services signature
• I've used "stateid" as field name for the "state class (result of $attempt->get_question_state_class())" as this state identifier is used for both classes and string ids, I can rename it to something more suitable if required.