Fix NPE when activity launch options are created before taskbaer init

Change-Id: Ibb8cf96ad4e528754aeb98ff0a702af2412e1052
Test: init
Fixes: 355231499
Flag: com.android.launcher3.enable_scaling_reveal_home_animation
diff --git a/quickstep/src/com/android/launcher3/taskbar/LauncherTaskbarUIController.java b/quickstep/src/com/android/launcher3/taskbar/LauncherTaskbarUIController.java
index 93a023d..252ebf7 100644
--- a/quickstep/src/com/android/launcher3/taskbar/LauncherTaskbarUIController.java
+++ b/quickstep/src/com/android/launcher3/taskbar/LauncherTaskbarUIController.java
@@ -272,6 +272,10 @@
      * app launch animation.
      */
     public void setIgnoreInAppFlagForSync(boolean enabled) {
+        if (mControllers == null) {
+            // This method can be called before init() is called.
+            return;
+        }
         mControllers.taskbarStashController.updateStateForFlag(FLAG_IGNORE_IN_APP, enabled);
     }