Add ServiceManager.registerForNotifications

Add the API to call into IServiceManager.registerForNotifications.

Test: pass
Change-Id: Ia74d8a1bd5be767a076560bf8ee4af3095b4623a

core/java/android/os/ServiceManager.java

@@ -297,6 +297,17 @@ public final class ServiceManager {
         return isDeclared(name) ? waitForService(name) : null;
     }
 
+    /**
+     * Register callback for service registration notifications.
+     *
+     * @throws RemoteException for underlying error.
+     * @hide
+     */
+    public static void registerForNotifications(
+            @NonNull String name, @NonNull IServiceCallback callback) throws RemoteException {
+        getIServiceManager().registerForNotifications(name, callback);
+    }
+
     /**
      * Return a list of all currently running services.
      * @return an array of all currently running services, or <code>null</code> in

core/java/android/os/ServiceManagerNative.java

@@ -78,7 +78,7 @@ class ServiceManagerProxy implements IServiceManager {
 
     public void registerForNotifications(String name, IServiceCallback cb)
             throws RemoteException {
-        throw new RemoteException();
+        mServiceManager.registerForNotifications(name, cb);
     }
 
     public void unregisterForNotifications(String name, IServiceCallback cb)