Fix crash on rotation

Load app/channel data early so that any open dialogs can be properly
reconstructed. Never call done on an entityheadercontroller with
an activity that's not yet started.

Test: robotests
Change-Id: Ib2b9f8f1985ef038959062204aaceff686f4ebcf
Fixes: 74114917

src/com/android/settings/notification/NotificationPreferenceController.java

@@ -96,7 +96,7 @@ public abstract class NotificationPreferenceController extends AbstractPreferenc
             if (preference != null) {
                 mPreference = preference;
             }
-            if (this instanceof Preference.OnPreferenceChangeListener) {
+            if (mPreference != null && this instanceof Preference.OnPreferenceChangeListener) {
                 mPreference.setOnPreferenceChangeListener(
                         (Preference.OnPreferenceChangeListener) this);
             }