Closes#14353
Squashed commit of the following:
commit edae0729f71ea3d3f9fa9c0d27c9effc042eb5a9
Author: Robert Muir <rmuir@apache.org>
Date: Thu Oct 29 14:13:42 2015 -0400
update sha1 and simplify test
commit 635c4f245d66ad353a16267c810e02b725553fad
Author: Robert Muir <rmuir@apache.org>
Date: Thu Oct 29 07:01:26 2015 -0400
Add threadgroup isolation.
Code with `modifyThread` and `modifyThreadGroup` may only modify
its own threadgroup (or an ancestor of that). This enforces
what is intended by the ThreadGroup class.
This has two immediate implications:
1. Code without these permissions (scripts) may not create or mess with threads
2. ES application threads cannot mess with Java system threads
ES puts all application threads in one single group today, but in the future
this can be organized better, and we will have more isolation in the system.