Make mCurrentPipTaskToken null when app crashes

PipTransition#mCurrentPipTaskToken needs to be nullified
after exit. Otherwise, we end up calling resetPrevPip()
without startEnterAnimation() later on when running PinnedStackTests.

Bug: 287989186
Test: atest PinnedStackTests
Test: run "adb shell am force-stop <pip activity package name>"
	after entering PiP, and then check for
	mCurrentPipTaskToken in sysdump
(cherry picked from commit 755d0c3df201f920634a473ae94b7eb1f0cad0a3)
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:931efa54c0a0d2419c68787a31f73dc5013d7b16)
Merged-In: Id869f78dbf85f009509082181590e224a6d7f893
Change-Id: Id869f78dbf85f009509082181590e224a6d7f893

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java
index b14c3c1..08da485 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java
@@ -1927,6 +1927,7 @@
         pw.println(innerPrefix + "mLeash=" + mLeash);
         pw.println(innerPrefix + "mState=" + mPipTransitionState.getTransitionState());
         pw.println(innerPrefix + "mPictureInPictureParams=" + mPictureInPictureParams);
+        mPipTransitionController.dump(pw, innerPrefix);
     }
 
     @Override

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java
index 73eb62a..e3d53fc 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java
@@ -72,6 +72,7 @@
 import com.android.wm.shell.transition.Transitions;
 import com.android.wm.shell.util.TransitionUtil;
 
+import java.io.PrintWriter;
 import java.util.Optional;
 
 /**
@@ -451,6 +452,9 @@
 
     @Override
     public void forceFinishTransition() {
+        // mFinishCallback might be null with an outdated mCurrentPipTaskToken
+        // for example, when app crashes while in PiP and exit transition has not started
+        mCurrentPipTaskToken = null;
         if (mFinishCallback == null) return;
         mFinishCallback.onTransitionFinished(null /* wct */, null /* callback */);
         mFinishCallback = null;
@@ -1137,4 +1141,12 @@
                 PipMenuController.ALPHA_NO_CHANGE);
         mPipMenuController.updateMenuBounds(destinationBounds);
     }
+
+    @Override
+    public void dump(PrintWriter pw, String prefix) {
+        final String innerPrefix = prefix + "  ";
+        pw.println(prefix + TAG);
+        pw.println(innerPrefix + "mCurrentPipTaskToken=" + mCurrentPipTaskToken);
+        pw.println(innerPrefix + "mFinishCallback=" + mFinishCallback);
+    }
 }

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java
index e1bcd70c..6362793 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java
@@ -42,6 +42,7 @@
 import com.android.wm.shell.sysui.ShellInit;
 import com.android.wm.shell.transition.Transitions;
 
+import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -283,4 +284,9 @@
          */
         void onPipTransitionCanceled(int direction);
     }
+
+    /**
+     * Dumps internal states.
+     */
+    public void dump(PrintWriter pw, String prefix) {}
 }