Add network created callback support

Create a network callback to notify network agent after
netd has created the network, so that the NetworkAgent may
wait for this callback and ensure the pre-work to communicate
with netd completed.

Bug: 178725261
Test: make update-api
Change-Id: I8c2ff7bd6980ae838abc5669f9419d62741b8666
Merged-In: I8c2ff7bd6980ae838abc5669f9419d62741b8666
diff --git a/framework/api/system-current.txt b/framework/api/system-current.txt
index 7733221..301387f 100644
--- a/framework/api/system-current.txt
+++ b/framework/api/system-current.txt
@@ -216,6 +216,7 @@
     method public void markConnected();
     method public void onAddKeepalivePacketFilter(int, @NonNull android.net.KeepalivePacketData);
     method public void onAutomaticReconnectDisabled();
+    method public void onNetworkCreated();
     method public void onNetworkUnwanted();
     method public void onQosCallbackRegistered(int, @NonNull android.net.QosFilter);
     method public void onQosCallbackUnregistered(int);