Pausing the transient hide activity with user leaving hint

Activity#onUserLeaveHint was not called while swiping up to home
since the activity was directly added to stopping list when
transient launch transition completed.

The code added in commit 0572aac to send task-stack-changed
event while finishing transition was also updated. It is not
needed if the activity is scheduled to be paused by TaskFragment
#startPausing since the task-stack changed is called after pause
completed. However, it is still needed if the activity enters
auto-pip when transition finishes.

Bug: 274576791
Test: swipe up to home
Change-Id: Idf664a93e95471d83c0964dc67ab384521f78b24

services/core/java/com/android/server/wm/ActivityRecord.java

@@ -6025,6 +6025,8 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
             // An activity must be in the {@link PAUSING} state for the system to validate
             // the move to {@link PAUSED}.
             setState(PAUSING, "makeActiveIfNeeded");
+            EventLogTags.writeWmPauseActivity(mUserId, System.identityHashCode(this),
+                    shortComponentName, "userLeaving=false", "make-active");
             try {
                 mAtmService.getLifecycleManager().scheduleTransaction(app.getThread(), token,
                         PauseActivityItem.obtain(finishing, false /* userLeaving */,

services/core/java/com/android/server/wm/Transition.java

@@ -783,7 +783,9 @@ class Transition implements BLASTSyncEngine.TransactionReadyListener {
      *         a chance we won't thus legacy-entry (via pause+userLeaving) will return false.
      */
     private boolean checkEnterPipOnFinish(@NonNull ActivityRecord ar) {
-        if (!mCanPipOnFinish || !ar.isVisible() || ar.getTask() == null) return false;
+        if (!mCanPipOnFinish || !ar.isVisible() || ar.getTask() == null || !ar.isState(RESUMED)) {
+            return false;
+        }
 
         if (ar.pictureInPictureArgs != null && ar.pictureInPictureArgs.isAutoEnterEnabled()) {
             if (didCommitTransientLaunch()) {
@@ -796,18 +798,14 @@ class Transition implements BLASTSyncEngine.TransactionReadyListener {
         }
 
         // Legacy pip-entry (not via isAutoEnterEnabled).
-        boolean canPip = ar.getDeferHidingClient();
-        if (!canPip && didCommitTransientLaunch()) {
+        if (didCommitTransientLaunch() && ar.supportsPictureInPicture()) {
             // force enable pip-on-task-switch now that we've committed to actually launching to the
             // transient activity, and then recalculate whether we can attempt pip.
             ar.supportsEnterPipOnTaskSwitch = true;
-            canPip = ar.checkEnterPictureInPictureState(
-                    "finishTransition", true /* beforeStopping */)
-                    && ar.isState(RESUMED);
         }
-        if (!canPip) return false;
+
         try {
-            // Legacy PIP-enter requires pause event with user-leaving.
+            // If not going auto-pip, the activity should be paused with user-leaving.
             mController.mAtm.mTaskSupervisor.mUserLeaving = true;
             ar.getTaskFragment().startPausing(false /* uiSleeping */,
                     null /* resuming */, "finishTransition");
@@ -851,6 +849,7 @@ class Transition implements BLASTSyncEngine.TransactionReadyListener {
 
         boolean hasParticipatedDisplay = false;
         boolean hasVisibleTransientLaunch = false;
+        boolean enterAutoPip = false;
         // Commit all going-invisible containers
         for (int i = 0; i < mParticipants.size(); ++i) {
             final WindowContainer<?> participant = mParticipants.valueAt(i);
@@ -886,6 +885,8 @@ class Transition implements BLASTSyncEngine.TransactionReadyListener {
                         }
                         ar.commitVisibility(false /* visible */, false /* performLayout */,
                                 true /* fromTransition */);
+                    } else {
+                        enterAutoPip = true;
                     }
                 }
                 if (mChanges.get(ar).mVisible != visibleAtTransitionEnd) {
@@ -940,8 +941,10 @@ class Transition implements BLASTSyncEngine.TransactionReadyListener {
         }
 
         if (hasVisibleTransientLaunch) {
-            // Notify the change about the transient-below task that becomes invisible.
-            mController.mAtm.getTaskChangeNotificationController().notifyTaskStackChanged();
+            // Notify the change about the transient-below task if entering auto-pip.
+            if (enterAutoPip) {
+                mController.mAtm.getTaskChangeNotificationController().notifyTaskStackChanged();
+            }
             // Prevent spurious background app switches.
             mController.mAtm.stopAppSwitches();
             // The end of transient launch may not reorder task, so make sure to compute the latest