Move handling of package changes to a background thread.

Helps get rid of some jank when installing applications.

Change-Id: I97d0022f82d67796e334d37086e5911dd6ca6b62
diff --git a/services/java/com/android/server/DevicePolicyManagerService.java b/services/java/com/android/server/DevicePolicyManagerService.java
index d8e3d59..eb33060 100644
--- a/services/java/com/android/server/DevicePolicyManagerService.java
+++ b/services/java/com/android/server/DevicePolicyManagerService.java
@@ -451,7 +451,7 @@
     public DevicePolicyManagerService(Context context) {
         mContext = context;
         mMonitor = new MyPackageMonitor();
-        mMonitor.register(context, true);
+        mMonitor.register(context, null, true);
         mWakeLock = ((PowerManager)context.getSystemService(Context.POWER_SERVICE))
                 .newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "DPM");
         IntentFilter filter = new IntentFilter();