[TL02]Remove hidden API usage of NetworkAgent

The connection service will become the mainline module.
Remove the hidden API usage of NetworkAgent.

Bug: 170598012
CTS-Coverage-Bug: 170598012
Test: atest FrameworksNetTests FrameworksTelephonyTests
      atest FrameworksWifiTests
Change-Id: I4e4040ae7f94bdf479c7df9ec2ffabafbe06331c
4 files changed
tree: 824f6d56851d51cf7ec09f9dcf0ea55923de0ca3
  1. framework/
  2. service/
  3. OWNERS