API review: make exception class and Builder final

- InvalidPacketException exception class should be final
- NetworkCapabilities.Builder should be final

Bug: 152203926
Test: atest FrameworksNetTests
Change-Id: If9b799151aff6d41c9bcd8bb86c65a58e46bad73
2 files changed
tree: 14f5cf95cf9d496629e5a96a2d909dcd6cf1d40e
  1. core/
  2. services/
  3. tests/