[JS01]Remove hidden API usage of Connectivity Sevice

The Connectivity service will become the mainline module.
Therefore, remove the caller of using Connectivity's
hidden API outside the module and expose the required
connectivity API used in Jobscheduler.

Bug: 183456204
CTS-Coverage-Bug: 170598012
Test: atest JobStoreTest
Change-Id: Ie6bc81ff382fb242b98f35d28a96defc207c7987

framework/src/android/net/ConnectivityManager.java

@@ -1083,8 +1083,7 @@ public class ConnectivityManager {
      *
      * @return a {@link Network} object for the current default network for the
      *         given UID or {@code null} if no default network is currently active
-     *
-     * @hide
+     * TODO: b/183465229 Cleanup getActiveNetworkForUid once b/165835257 is fixed
      */
     @RequiresPermission(android.Manifest.permission.NETWORK_STACK)
     @Nullable