Derive LauncherAppsService from SystemService

And encapsulate the aidl interface implementation.

Change-Id: Id9a2544b411648e2596de18682079a64e95b0710
diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index 27098e7..9174c0c 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -998,8 +998,7 @@
 
             try {
                 Slog.i(TAG, "LauncherAppsService");
-                LauncherAppsService las = new LauncherAppsService(context);
-                ServiceManager.addService(Context.LAUNCHER_APPS_SERVICE, las);
+                mSystemServiceManager.startService(LauncherAppsService.class);
             } catch (Throwable t) {
                 reportWtf("starting LauncherAppsService", t);
             }