Remove unused NetworkPolicyManagerInternal in CS am: c850635440 am: 143739703d

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

Change-Id: I8e19008eb864b2cafc1725e96b85c51372913c22
tree: 05034deeb1760a449c14e882938398d5da406943
  1. core/
  2. framework/
  3. service/
  4. services/
  5. tests/
  6. OWNERS