How do permissions affect create on transition functions?

Description

A post function runs under with the permissions of the user that initiated the transition. The post functions only do actions that the user is permitted to do. The post function runs after the transition completes and so errors that occur during the post function only report errors via the server log. Specifically, this means that errors are effectively ignored from the user's perspective. The workflow designer needs to construct post functions with this in mind. For instance, this could include putting conditions on that transition to prevent the transition from happening if the user does not have enough permission to do all the things necessary in the post function.

Details

1. Create issue - the user needs create issue permission. The create will fail if user does not have permission.
2. Add watchers - the user needs manage watchers permission. Watchers will not be added if the user does not have permission. In addition, only watchers that have permission to browse the project will be added, others will be ignored.
3. Add link - the user needs link issue permission. No link will be added if the user does not have permission.
4. Set issue security level - the user needs set issue security permission. Issue security will not be set if the user does not have permission. This only applies to create issue as subtasks inherit security level from their parent.