For example the dependecy chain is the following: A->B->C. When a
question (A) depends on another dependent item (B) and B hasn't
displayed (because of C's response), the $value for the B's response
will be null. In this case the can_see_item() method returned
null. Because the can_see_item() returned null (not false), the
get_pages() method displayed the question A, because it checks for
explicit false: $this->can_see_item($item) !== false.
Now, false is also returned, if the dependent question is not visible.
Update mod_feedback_core_calendar_provide_event_action function to add a new userid parameter
Add userid to check capabilities, etc. to feedback completion and structure.
The feedback module lets you alternate between responses being anonymised and
not anonymised. When the module is in anonymous mode, its possible for a single
user to make multiple responses.
However when the activity is switched to non-anon mode, if a user leaves a
follow up feedback, one of their previously anonymous responses is used, so
their new response stays anonymous and their old anon response is lost.
This change lets them leave a new non-anonymised feedback entry and retains all
previous anonymous responses instead of incorrectly reusing one of their anon
ones at random.
