am d511bc17: Merge "[ActivityManager] Fix a bug: unable to start activity after starting activities during screen off."

* commit 'd511bc17d614b1291f1b85f84180c1db157d2790':
  [ActivityManager] Fix a bug: unable to start activity after starting activities during screen off.
diff --git a/services/java/com/android/server/am/ActivityStack.java b/services/java/com/android/server/am/ActivityStack.java
index b42bce2..07c2201 100755
--- a/services/java/com/android/server/am/ActivityStack.java
+++ b/services/java/com/android/server/am/ActivityStack.java
@@ -2625,6 +2625,9 @@
         if (mResumedActivity == r) {
             mResumedActivity = null;
         }
+        if (mPausingActivity == r) {
+            mPausingActivity = null;
+        }
         if (mService.mFocusedActivity == r) {
             mService.mFocusedActivity = null;
         }