Make LegacyTypeTracker testable

...and add basic trivial tests for it.

Test: this, and ConnectivityServiceTest
Bug: 62650382
Change-Id: Ie7ca938e6f66f1b15feb6ed93afa0aebb20884ae
3 files changed
tree: b83f7abac326c1ceb14716c84cd4e860d06beb7c
  1. core/
  2. services/
  3. tests/