Add null check to offsetCaptionLocation

There is currently a bug that is causing window decorations to exist
even after the task they belong to has been deleted. This is causing a
null pointer exception here since we are searching for the TaskInfo of
an already deleted task using TaskOrganizer#getRunningTaskInfo which
causes it to return null.

Bug: 311273642
Test: Move task around and change windowing modes to make sure SysUi is
no longer crashing

Change-Id: I4972f041d36e345a40a026bdfc4c4077ff13dfe0

1 files changed, 4 insertions, 2 deletions

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/DesktopModeWindowDecoration.java b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/DesktopModeWindowDecoration.java
index e1d177af2331..6ec91e0e28dd 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/DesktopModeWindowDecoration.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/DesktopModeWindowDecoration.java
@@ -548,8 +548,10 @@ public class DesktopModeWindowDecoration extends WindowDecoration<WindowDecorLin
      */
     private PointF offsetCaptionLocation(MotionEvent ev) {
         final PointF result = new PointF(ev.getX(), ev.getY());
-        final Point positionInParent = mTaskOrganizer.getRunningTaskInfo(mTaskInfo.taskId)
-                .positionInParent;
+        final ActivityManager.RunningTaskInfo taskInfo =
+                mTaskOrganizer.getRunningTaskInfo(mTaskInfo.taskId);
+        if (taskInfo == null) return result;
+        final Point positionInParent = taskInfo.positionInParent;
         result.offset(-mRelayoutParams.mCaptionX, -mRelayoutParams.mCaptionY);
         result.offset(-positionInParent.x, -positionInParent.y);
         return result;