Fixe the problem of invalid switch preference

- SettingsMainSwithBar will be recreated after the page is resumed.
  We should keep the OnMainSwitchChangeListener for
  SettingsMainSwitchPreference and re-register the listeners after
  the page is resumed.

Fix: 228930107
Fix: 222384287
Test: Manually test and see the UI
Change-Id: I9b57053989e611288cf4814b2a0ecbf9e3c55145

src/com/android/settings/widget/SettingsMainSwitchPreference.java

@@ -254,7 +254,5 @@ public class SettingsMainSwitchPreference extends TwoStatePreference implements
         for (OnMainSwitchChangeListener listener : mSwitchChangeListeners) {
             mMainSwitchBar.addOnSwitchChangeListener(listener);
         }
-        mBeforeCheckedChangeListeners.clear();
-        mSwitchChangeListeners.clear();
     }
 }