Remove unused NetworkPolicyManagerInternal in CS am: c850635440

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1646969

Change-Id: I5a838b1017d1648e67576bfd7940ea9161b2c764
tree: 05034deeb1760a449c14e882938398d5da406943
  1. core/
  2. framework/
  3. service/
  4. services/
  5. tests/
  6. OWNERS