Fix crash on second screenshot.

(Work around new animator.end() behavior.)

Bug: 25601129
Change-Id: I9e5d9fc72cffa909dfd98ad80b7812df2a0e178a
diff --git a/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java b/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
index 9e3cf37..e6a291c 100644
--- a/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
+++ b/packages/SystemUI/src/com/android/systemui/screenshot/GlobalScreenshot.java
@@ -594,7 +594,9 @@
 
         // Setup the animation with the screenshot just taken
         if (mScreenshotAnimation != null) {
-            mScreenshotAnimation.end();
+            if (mScreenshotAnimation.isStarted()) {
+                mScreenshotAnimation.end();
+            }
             mScreenshotAnimation.removeAllListeners();
         }