Reapply "Add LocalNetworkConfig"

framework/aidl-export/android/net/LocalNetworkConfig.aidl

framework/src/android/net/ConnectivityManager.java

framework/src/android/net/IConnectivityManager.aidl

framework/src/android/net/INetworkAgentRegistry.aidl

framework/src/android/net/LocalNetworkConfig.java

framework/src/android/net/MulticastRoutingConfig.java

framework/src/android/net/NetworkAgent.java

service/src/com/android/server/ConnectivityService.java

...src/com/android/server/connectivity/NetworkAgentInfo.java

tests/cts/net/src/android/net/cts/NetworkAgentTest.kt

...unit/java/com/android/server/ConnectivityServiceTest.java

...va/com/android/server/connectivity/LingerMonitorTest.java

tests/unit/java/com/android/server/connectivity/VpnTest.java

...android/server/connectivityservice/CSKeepConnectedTest.kt

...d/server/connectivityservice/CSLocalAgentCreationTests.kt

...m/android/server/connectivityservice/CSLocalAgentTests.kt

...android/server/connectivityservice/base/CSAgentWrapper.kt

...ava/com/android/server/connectivityservice/base/CSTest.kt