commit 95f8f0ed6508c29180900e6c813e146caa200600
author Winson Chung <winsonc@google.com> Fri Mar 24 09:20:17 2017 -0700
committer Winson Chung <winsonc@google.com> Fri Mar 24 09:20:17 2017 -0700
tree 237672327596bc1f3ac673f781fb892f94ec987d
parent adb9fcde8514d28c9ea5e5ac988d477a77b895c8

Prevent cleaning up and resuming null activity when task is reparented.

- If reparenting a task with no running activities, ensure that we don't
  try to clean up the null activity record from the stack.  In addition,
  once the task is reparented, skip the attempt to front if the activity
  is null.

Bug: 36508639
Test: android.server.cts.ActivityManagerPinnedStackTests
Change-Id: I58d4d600523ac263d0be1ee8d09cfc4d94bef664

services/core/java/com/android/server/am/TaskRecord.java

diff --git a/services/core/java/com/android/server/am/TaskRecord.java b/services/core/java/com/android/server/am/TaskRecord.java
index a668fea..bd32df3 100644
--- a/services/core/java/com/android/server/am/TaskRecord.java
+++ b/services/core/java/com/android/server/am/TaskRecord.java
@@ -617,15 +617,15 @@
         boolean kept = true;
         try {
             final ActivityRecord r = topRunningActivityLocked();
-            final boolean wasFocused = supervisor.isFocusedStack(sourceStack)
+            final boolean wasFocused = r != null && supervisor.isFocusedStack(sourceStack)
                     && (topRunningActivityLocked() == r);
-            final boolean wasResumed = sourceStack.mResumedActivity == r;
-            final boolean wasPaused = sourceStack.mPausingActivity == r;
+            final boolean wasResumed = r != null && sourceStack.mResumedActivity == r;
+            final boolean wasPaused = r != null && sourceStack.mPausingActivity == r;
 
             // In some cases the focused stack isn't the front stack. E.g. pinned stack.
             // Whenever we are moving the top activity from the front stack we want to make sure to
             // move the stack to the front.
-            final boolean wasFront = supervisor.isFrontStackOnDisplay(sourceStack)
+            final boolean wasFront = r != null && supervisor.isFrontStackOnDisplay(sourceStack)
                     && (sourceStack.topRunningActivityLocked() == r);
 
             // Adjust the position for the new parent stack as needed.
@@ -667,8 +667,10 @@
             // new stack by moving the stack to the front.
             final boolean moveStackToFront = moveStackMode == REPARENT_MOVE_STACK_TO_FRONT
                     || (moveStackMode == REPARENT_KEEP_STACK_AT_FRONT && (wasFocused || wasFront));
-            toStack.moveToFrontAndResumeStateIfNeeded(r, moveStackToFront, wasResumed, wasPaused,
-                    reason);
+            if (r != null) {
+                toStack.moveToFrontAndResumeStateIfNeeded(r, moveStackToFront, wasResumed,
+                        wasPaused, reason);
+            }
             if (!animate) {
                 toStack.mNoAnimActivities.add(topActivity);
             }