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/InputMethodManagerService.java b/services/java/com/android/server/InputMethodManagerService.java
index a474cec..43c2292 100644
--- a/services/java/com/android/server/InputMethodManagerService.java
+++ b/services/java/com/android/server/InputMethodManagerService.java
@@ -594,7 +594,7 @@
         }
         mImListManager = new InputMethodAndSubtypeListManager(context, this);
 
-        (new MyPackageMonitor()).register(mContext, true);
+        (new MyPackageMonitor()).register(mContext, null, true);
 
         IntentFilter screenOnOffFilt = new IntentFilter();
         screenOnOffFilt.addAction(Intent.ACTION_SCREEN_ON);