Make public the registerDefaultNetworkCallback API

Change-Id: I89d7a6f49f5d6a0da3402a07407b0f8d93181b4f
diff --git a/api/current.txt b/api/current.txt
index f4efc92..18388b2 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -23452,6 +23452,7 @@
     method public boolean isActiveNetworkMetered();
     method public boolean isDefaultNetworkActive();
     method public static deprecated boolean isNetworkTypeValid(int);
+    method public void registerDefaultNetworkCallback(android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.app.PendingIntent);
     method public void releaseNetworkRequest(android.app.PendingIntent);
diff --git a/api/system-current.txt b/api/system-current.txt
index 521b853..051ed04 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -25188,6 +25188,7 @@
     method public boolean isDefaultNetworkActive();
     method public static deprecated boolean isNetworkTypeValid(int);
     method public boolean isTetheringSupported();
+    method public void registerDefaultNetworkCallback(android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.app.PendingIntent);
     method public void releaseNetworkRequest(android.app.PendingIntent);
diff --git a/api/test-current.txt b/api/test-current.txt
index 7ae0f97..fe7b4d3 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -23517,6 +23517,7 @@
     method public boolean isActiveNetworkMetered();
     method public boolean isDefaultNetworkActive();
     method public static deprecated boolean isNetworkTypeValid(int);
+    method public void registerDefaultNetworkCallback(android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.net.ConnectivityManager.NetworkCallback);
     method public void registerNetworkCallback(android.net.NetworkRequest, android.app.PendingIntent);
     method public void releaseNetworkRequest(android.app.PendingIntent);
diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index f0673ff..b452341 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -3021,7 +3021,6 @@
      *
      * @param networkCallback The {@link NetworkCallback} that the system will call as the
      *                        system default network changes.
-     * @hide
      */
     public void registerDefaultNetworkCallback(NetworkCallback networkCallback) {
         // This works because if the NetworkCapabilities are null,