Move kernelToTag to NetworkStatsFactory. am: adab7b1cc3 am: 4f3022fa09 am: a2af9dbf3d am: 6e3a218678

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1964913

Change-Id: I0d7a250e321ff80dc4ab94c57c6fb9ea7c793677
tree: 81d975cc541a53922e56491bf81daf0813192c2b
  1. framework/
  2. framework-t/
  3. service-t/
  4. services/
  5. tests/