Fix NPE

Bug: 6394159
Change-Id: Idd7c94b4c8698a9f6a35e5da5ea8306a952084e8

src/com/android/launcher2/Launcher.java

diff --git a/src/com/android/launcher2/Launcher.java b/src/com/android/launcher2/Launcher.java
index 2829e3c..7b9b36e 100644
--- a/src/com/android/launcher2/Launcher.java
+++ b/src/com/android/launcher2/Launcher.java
@@ -2452,7 +2452,9 @@
                     fromView.setVisibility(View.GONE);
                     dispatchOnLauncherTransitionEnd(fromView, animated, true);
                     dispatchOnLauncherTransitionEnd(toView, animated, true);
-                    mWorkspace.hideScrollingIndicator(false);
+                    if (mWorkspace != null) {
+                        mWorkspace.hideScrollingIndicator(false);
+                    }
                     if (onCompleteRunnable != null) {
                         onCompleteRunnable.run();
                     }