From 311ecba9818a6b09a0061a3f3fae84043f333f40 Mon Sep 17 00:00:00 2001
From: Robert Carr <racarr@google.com>
Date: Wed, 27 Apr 2016 12:59:45 -0700
Subject: [PATCH] Fix crash when docking.

ViewRootImpl may be null at this point if
we didn't preserve. Sorry about the churn.

Bug: 28413589
Change-Id: Iebfd819490252b52332d94ccefbddfae160087cf
---
 core/java/android/app/ActivityThread.java | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 0764ff41efaf3..f7c0b4c32bc90 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -3479,7 +3479,9 @@ public final class ActivityThread {
                     // the decor view we have to notify the view root that the
                     // callbacks may have changed.
                     ViewRootImpl impl = decor.getViewRootImpl();
-                    impl.notifyChildRebuilt();
+                    if (impl != null) {
+                        impl.notifyChildRebuilt();
+                    }
                 }
                 if (a.mVisibleFromClient && !a.mWindowAdded) {
                     a.mWindowAdded = true;