Refactor the app updates so that it doesn't rely on the package name.

This will be needed for the upcoming change to update the icons with the
grayed out when the SD card goes away.

src/com/android/launcher2/LauncherApplication.java

@@ -43,6 +43,10 @@ public class LauncherApplication extends Application {
         filter.addAction(Intent.ACTION_PACKAGE_CHANGED);
         filter.addDataScheme("package");
         registerReceiver(mModel, filter);
+        filter = new IntentFilter();
+        filter.addAction(Intent.ACTION_EXTERNAL_APPLICATIONS_AVAILABLE);
+        filter.addAction(Intent.ACTION_EXTERNAL_APPLICATIONS_UNAVAILABLE);
+        registerReceiver(mModel, filter);
 
         // Register for changes to the favorites
         ContentResolver resolver = getContentResolver();