Merge "Addition separation of adding vs. reparenting activity"
diff --git a/services/core/java/com/android/server/am/ActivityRecord.java b/services/core/java/com/android/server/am/ActivityRecord.java
index 962056f..3573b8b 100644
--- a/services/core/java/com/android/server/am/ActivityRecord.java
+++ b/services/core/java/com/android/server/am/ActivityRecord.java
@@ -37,6 +37,8 @@
 import static android.content.pm.ActivityInfo.FLAG_SHOW_FOR_ALL_USERS;
 import static android.content.pm.ActivityInfo.FLAG_STATE_NOT_NEEDED;
 import static android.content.pm.ActivityInfo.LAUNCH_MULTIPLE;
+import static android.content.pm.ActivityInfo.LAUNCH_SINGLE_INSTANCE;
+import static android.content.pm.ActivityInfo.LAUNCH_SINGLE_TASK;
 import static android.content.pm.ActivityInfo.LAUNCH_SINGLE_TOP;
 import static android.content.pm.ActivityInfo.RESIZE_MODE_FORCE_RESIZEABLE;
 import static android.content.pm.ActivityInfo.RESIZE_MODE_RESIZEABLE;
@@ -773,7 +775,10 @@
 
         // Remove the activity from the old task and add it to the new task
         prevTask.removeActivity(this);
-        setTask(newTask, null);
+        // TODO(b/34179495): This should really be set to null in removeActivity() call above,
+        // but really bad things that I can't track down right now happen when I do that.
+        // So, setting it here now and will change later when there is time for investigation.
+        task = null;
         newTask.addActivityAtIndex(position, this);
     }
 
@@ -821,19 +826,8 @@
         }
     }
 
-    void setTask(TaskRecord newTask, TaskRecord taskToAffiliateWith) {
-        if (task != null && task.removeActivity(this) && task != newTask
-                && task.getStack() != null) {
-            task.getStack().removeTask(task, "setTask");
-        }
-        task = newTask;
-        setTaskToAffiliateWith(taskToAffiliateWith);
-    }
-
     void setTaskToAffiliateWith(TaskRecord taskToAffiliateWith) {
-        if (taskToAffiliateWith != null &&
-                launchMode != ActivityInfo.LAUNCH_SINGLE_INSTANCE &&
-                launchMode != ActivityInfo.LAUNCH_SINGLE_TASK) {
+        if (launchMode != LAUNCH_SINGLE_INSTANCE && launchMode != LAUNCH_SINGLE_TASK) {
             task.setTaskToAffiliateWith(taskToAffiliateWith);
         }
     }
diff --git a/services/core/java/com/android/server/am/ActivityStack.java b/services/core/java/com/android/server/am/ActivityStack.java
index 54082ea..10d108b 100644
--- a/services/core/java/com/android/server/am/ActivityStack.java
+++ b/services/core/java/com/android/server/am/ActivityStack.java
@@ -2775,7 +2775,12 @@
         // Slot the activity into the history stack and proceed
         if (DEBUG_ADD_REMOVE) Slog.i(TAG, "Adding activity " + r + " to stack to task " + task,
                 new RuntimeException("here").fillInStackTrace());
-        r.createWindowContainer();
+        // TODO: Need to investigate if it is okay for the controller to already be created by the
+        // time we get to this point. I think it is, but need to double check.
+        // Use test in b/34179495 to trace the call path.
+        if (r.getWindowContainerController() == null) {
+            r.createWindowContainer();
+        }
         task.setFrontOfTask();
 
         if (!isHomeOrRecentsStack() || numActivities() > 0) {
@@ -2952,8 +2957,7 @@
                             + targetTask + " Callers=" + Debug.getCallers(4));
                     if (DEBUG_TASKS) Slog.v(TAG_TASKS,
                             "Pushing next activity " + p + " out to target's task " + target.task);
-                    p.setTask(targetTask, null);
-                    targetTask.addActivityAtBottom(p);
+                    p.reparent(targetTask, 0 /* position - bottom */, "resetTargetTaskIfNeeded");
                 }
 
                 mWindowContainerController.positionChildAtBottom(
diff --git a/services/core/java/com/android/server/am/ActivityStarter.java b/services/core/java/com/android/server/am/ActivityStarter.java
index 73ef88b..c2fc9dc 100644
--- a/services/core/java/com/android/server/am/ActivityStarter.java
+++ b/services/core/java/com/android/server/am/ActivityStarter.java
@@ -1615,7 +1615,7 @@
                     mNewTaskInfo != null ? mNewTaskInfo : mStartActivity.info,
                     mNewTaskIntent != null ? mNewTaskIntent : mIntent, mVoiceSession,
                     mVoiceInteractor, !mLaunchTaskBehind /* toTop */, mStartActivity.mActivityType);
-            mStartActivity.setTask(task, taskToAffiliate);
+            addOrReparentStartingActivity(task, "setTaskFromReuseOrCreateNewTask - mReuseTask");
             if (mLaunchBounds != null) {
                 final int stackId = mTargetStack.mStackId;
                 if (StackId.resizeStackWithLaunchBounds(stackId)) {
@@ -1625,11 +1625,14 @@
                     mStartActivity.task.updateOverrideConfiguration(mLaunchBounds);
                 }
             }
-            if (DEBUG_TASKS) Slog.v(TAG_TASKS,
-                    "Starting new activity " +
-                            mStartActivity + " in new task " + mStartActivity.task);
+            if (DEBUG_TASKS) Slog.v(TAG_TASKS, "Starting new activity " + mStartActivity
+                    + " in new task " + mStartActivity.task);
         } else {
-            mStartActivity.setTask(mReuseTask, taskToAffiliate);
+            addOrReparentStartingActivity(mReuseTask, "setTaskFromReuseOrCreateNewTask");
+        }
+
+        if (taskToAffiliate != null) {
+            mStartActivity.setTaskToAffiliateWith(taskToAffiliate);
         }
 
         if (mSupervisor.isLockTaskModeViolation(mStartActivity.task)) {
@@ -1719,7 +1722,7 @@
 
         // An existing activity is starting this new activity, so we want to keep the new one in
         // the same task as the one that is starting it.
-        mStartActivity.setTask(sourceTask, null);
+        addOrReparentStartingActivity(sourceTask, "setTaskFromSourceRecord");
         if (DEBUG_TASKS) Slog.v(TAG_TASKS, "Starting new activity " + mStartActivity
                 + " in existing task " + mStartActivity.task + " from source " + mSourceRecord);
         return START_SUCCESS;
@@ -1752,7 +1755,8 @@
         // Check whether we should actually launch the new activity in to the task,
         // or just reuse the current activity on top.
         ActivityRecord top = mInTask.getTopActivity();
-        if (top != null && top.realActivity.equals(mStartActivity.realActivity) && top.userId == mStartActivity.userId) {
+        if (top != null && top.realActivity.equals(mStartActivity.realActivity)
+                && top.userId == mStartActivity.userId) {
             if ((mLaunchFlags & FLAG_ACTIVITY_SINGLE_TOP) != 0
                     || mLaunchSingleTop || mLaunchSingleTask) {
                 ActivityStack.logStartActivity(AM_NEW_INTENT, top, top.task);
@@ -1761,7 +1765,8 @@
                     // anything if that is the case, so this is it!
                     return START_RETURN_INTENT_TO_CALLER;
                 }
-                top.deliverNewIntentLocked(mCallingUid, mStartActivity.intent, mStartActivity.launchedFromPackage);
+                top.deliverNewIntentLocked(mCallingUid, mStartActivity.intent,
+                        mStartActivity.launchedFromPackage);
                 return START_DELIVERED_TO_TOP;
             }
         }
@@ -1773,9 +1778,9 @@
             return START_TASK_TO_FRONT;
         }
 
-        mStartActivity.setTask(mInTask, null);
-        if (DEBUG_TASKS) Slog.v(TAG_TASKS,
-                "Starting new activity " + mStartActivity + " in explicit task " + mStartActivity.task);
+        addOrReparentStartingActivity(mInTask, "setTaskFromInTask");
+        if (DEBUG_TASKS) Slog.v(TAG_TASKS, "Starting new activity " + mStartActivity
+                + " in explicit task " + mStartActivity.task);
 
         return START_SUCCESS;
     }
@@ -1790,10 +1795,18 @@
         final TaskRecord task = (prev != null) ? prev.task : mTargetStack.createTaskRecord(
                 mSupervisor.getNextTaskIdForUserLocked(mStartActivity.userId), mStartActivity.info,
                 mIntent, null, null, true, mStartActivity.mActivityType);
-        mStartActivity.setTask(task, null);
-        mStartActivity.task.getStack().positionChildWindowContainerAtTop(mStartActivity.task);
-        if (DEBUG_TASKS) Slog.v(TAG_TASKS,
-                "Starting new activity " + mStartActivity + " in new guessed " + mStartActivity.task);
+        addOrReparentStartingActivity(task, "setTaskToCurrentTopOrCreateNewTask");
+        mTargetStack.positionChildWindowContainerAtTop(task);
+        if (DEBUG_TASKS) Slog.v(TAG_TASKS, "Starting new activity " + mStartActivity
+                + " in new guessed " + mStartActivity.task);
+    }
+
+    private void addOrReparentStartingActivity(TaskRecord parent, String reason) {
+        if (mStartActivity.task == null) {
+            parent.addActivityToTop(mStartActivity);
+        } else {
+            mStartActivity.reparent(parent, parent.mActivities.size() /* top */, reason);
+        }
     }
 
     private int adjustLaunchFlagsToDocumentMode(ActivityRecord r, boolean launchSingleInstance,
diff --git a/services/core/java/com/android/server/am/TaskRecord.java b/services/core/java/com/android/server/am/TaskRecord.java
index fef4073..9e09cbb 100644
--- a/services/core/java/com/android/server/am/TaskRecord.java
+++ b/services/core/java/com/android/server/am/TaskRecord.java
@@ -51,6 +51,7 @@
 import com.android.internal.app.IVoiceInteractor;
 import com.android.internal.util.XmlUtils;
 
+import com.android.server.wm.AppWindowContainerController;
 import com.android.server.wm.TaskWindowContainerController;
 import com.android.server.wm.TaskWindowContainerListener;
 
@@ -1033,6 +1034,12 @@
      * be in the current task or unparented to any task.
      */
     void addActivityAtIndex(int index, ActivityRecord r) {
+        if (r.task != null && r.task != this) {
+            throw new IllegalArgumentException("Can not add r=" + " to task=" + this
+                    + " current parent=" + r.task);
+        }
+        r.task = this;
+
         // Remove r first, and if it wasn't already in the list and it's fullscreen, count it.
         if (!mActivities.remove(r) && r.fullscreen) {
             // Was not previously in list.
@@ -1063,6 +1070,7 @@
             }
         }
 
+        index = Math.min(size, index);
         mActivities.add(index, r);
         updateEffectiveIntent();
         if (r.isPersistable()) {
@@ -1071,7 +1079,12 @@
 
         // Sync. with window manager
         updateOverrideConfigurationFromLaunchBounds();
-        mWindowContainerController.positionChildAt(r.getWindowContainerController(), index);
+        final AppWindowContainerController appController = r.getWindowContainerController();
+        if (appController != null) {
+            // Only attempt to move in WM if the child has a controller. It is possible we haven't
+            // created controller for the activity we are starting yet.
+            mWindowContainerController.positionChildAt(appController, index);
+        }
         r.onOverrideConfigurationSent();
     }