This restores previous behavior, where callbacks would not be called on
the IpClient handler thread.
Test: atest FrameworksNetTests NetworkStackTests
Test: flashed, WiFi works
Bug: 123062477
Change-Id: I3015566b0922d76ac7cf70579a1de3e033bf7b4a
Use the new NetworkObserverRegistry instead.
Test: atest FrameworksNetTests NetworkStackTests
Test: flashed, WiFi working fine
Bug: 112869080
Change-Id: If16ecfd6489f86afec67c22b4c3692cd68f4edbf
NetworkStackTests is run with a version of mockito that allows mocking
final methods, which broke mocking of the ConnectivityService.
Test: atest NetworkStackTests
Change-Id: I430fe12216c43a0c4265a504dbefafad37c09291