[PT02] Move static methods to ProxyTracker

No logic changes. Only changes are adding nullability annotations,
final modifiers, and adding an s in a comment.

Test: runtests
Change-Id: If4986a25bb36819de8ff459c4c0439c56d4e5a50
2 files changed
tree: 6af2de73561df60093c303fb0b734103c6baedf9
  1. core/
  2. services/
  3. tests/