From 0e7f7b38169090fcf3930690ee5398bfc6ba0083 Mon Sep 17 00:00:00 2001
From: Erik Wolsheimer <ewol@google.com>
Date: Fri, 29 Sep 2017 12:12:47 -0700
Subject: [PATCH] Prevent NPE at TaskStack#resetAnimationBackgroundAnimator

Bug: 67034123
Change-Id: Ie1c7d8371d146006bc98f3a1ccc25292771ae3f9
(cherry picked from commit 70f5a4a3e807bfe30cd88431207774b23369075c)
---
 services/core/java/com/android/server/wm/TaskStack.java | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/services/core/java/com/android/server/wm/TaskStack.java b/services/core/java/com/android/server/wm/TaskStack.java
index 4308ff9773984..6527883770051 100644
--- a/services/core/java/com/android/server/wm/TaskStack.java
+++ b/services/core/java/com/android/server/wm/TaskStack.java
@@ -923,7 +923,9 @@ public class TaskStack extends WindowContainer<Task> implements DimLayer.DimLaye
 
     void resetAnimationBackgroundAnimator() {
         mAnimationBackgroundAnimator = null;
-        mAnimationBackgroundSurface.hide();
+        if (mAnimationBackgroundSurface != null) {
+            mAnimationBackgroundSurface.hide();
+        }
     }
 
     void setAnimationBackground(WindowStateAnimator winAnimator, int color) {