Removes references to these deprecated attributes from the platform code:
* runtime.anonymous_student_id
* runtime.seed
* runtime.user_id
* runtime.user_is_staff
Related changes:
* Ensure that all platform XBlocks which use these attributes "need" the user service.
* ProblemBlock: Removes check for existence of runtime.seed attribute in preparation for removal of this attribute from ModuleSystem.
* edxnotes: Catches NoSuchServiceError just in case some XBlocks using notes don't have the user service.
* UserTagsService refactor: pass user and course_id on creation
(cherry picked from commit 753839276f)
bafc0cd91f