Don't removePluginListener() unless user is unlocked

This just crashes since we can't access SharedPreferences, and we don't
addPluginListener until onUserUnlocked() anyway.

Change-Id: I705498f859857a52a2cb5735201a652973b26d0b
diff --git a/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
index 71f8ba4..07537ed 100644
--- a/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
+++ b/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
@@ -391,12 +391,11 @@
 
     @Override
     public void onDestroy() {
-        PluginManagerWrapper.INSTANCE.get(getBaseContext()).removePluginListener(this);
-
         sIsInitialized = false;
         if (mDeviceState.isUserUnlocked()) {
             mInputConsumer.unregisterInputConsumer();
             mOverviewComponentObserver.onDestroy();
+            PluginManagerWrapper.INSTANCE.get(getBaseContext()).removePluginListener(this);
         }
         disposeEventHandlers();
         mDeviceState.destroy();