Remove obsolete desktop stashing for Desktop Windowing.

Bug: 309481654
Change-Id: I3694c72c34432563a83926cd795b54136222fbab
Flag: EXEMPT refactor since it is removing obsolete code with no changes to current behavior.
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
index 9bf9fa7..6af1504 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
@@ -41,15 +41,6 @@
     public static final boolean IS_DISPLAY_CHANGE_ENABLED = SystemProperties.getBoolean(
             "persist.wm.debug.desktop_change_display", false);
 
-
-    /**
-     * Flag to indicate that desktop stashing is enabled.
-     * When enabled, swiping home from desktop stashes the open apps. Next app that launches,
-     * will be added to the desktop.
-     */
-    private static final boolean IS_STASHING_ENABLED = SystemProperties.getBoolean(
-            "persist.wm.debug.desktop_stashing", false);
-
     /**
      * Flag to indicate whether to apply shadows to windows in desktop mode.
      */
@@ -109,14 +100,6 @@
     }
 
     /**
-     * Return {@code true} if desktop task stashing is enabled when going home.
-     * Allows users to use home screen to add tasks to desktop.
-     */
-    public static boolean isStashingEnabled() {
-        return IS_STASHING_ENABLED;
-    }
-
-    /**
      * Return whether to use window shadows.
      *
      * @param isFocusedWindow whether the window to apply shadows to is focused
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
index 2d508b2..6bbc8fe 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepository.kt
@@ -48,7 +48,6 @@
         val activeTasks: ArraySet<Int> = ArraySet(),
         val visibleTasks: ArraySet<Int> = ArraySet(),
         val minimizedTasks: ArraySet<Int> = ArraySet(),
-        var stashed: Boolean = false
     )
 
     // Token of the current wallpaper activity, used to remove it when the last task is removed
@@ -95,10 +94,8 @@
         visibleTasksListeners[visibleTasksListener] = executor
         displayData.keyIterator().forEach { displayId ->
             val visibleTasksCount = getVisibleTaskCount(displayId)
-            val stashed = isStashed(displayId)
             executor.execute {
                 visibleTasksListener.onTasksVisibilityChanged(displayId, visibleTasksCount)
-                visibleTasksListener.onStashedChanged(displayId, stashed)
             }
         }
     }
@@ -400,26 +397,6 @@
     }
 
     /**
-     * Update stashed status on display with id [displayId]
-     */
-    fun setStashed(displayId: Int, stashed: Boolean) {
-        val data = displayData.getOrCreate(displayId)
-        val oldValue = data.stashed
-        data.stashed = stashed
-        if (oldValue != stashed) {
-            KtProtoLog.d(
-                    WM_SHELL_DESKTOP_MODE,
-                    "DesktopTaskRepo: mark stashed=%b displayId=%d",
-                    stashed,
-                    displayId
-            )
-            visibleTasksListeners.forEach { (listener, executor) ->
-                executor.execute { listener.onStashedChanged(displayId, stashed) }
-            }
-        }
-    }
-
-    /**
      * Removes and returns the bounds saved before maximizing the given task.
      */
     fun removeBoundsBeforeMaximize(taskId: Int): Rect? {
@@ -433,13 +410,6 @@
         boundsBeforeMaximizeByTaskId.set(taskId, Rect(bounds))
     }
 
-    /**
-     * Check if display with id [displayId] has desktop tasks stashed
-     */
-    fun isStashed(displayId: Int): Boolean {
-        return displayData[displayId]?.stashed ?: false
-    }
-
     internal fun dump(pw: PrintWriter, prefix: String) {
         val innerPrefix = "$prefix  "
         pw.println("${prefix}DesktopModeTaskRepository")
@@ -455,7 +425,6 @@
             pw.println("${prefix}Display $displayId:")
             pw.println("${innerPrefix}activeTasks=${data.activeTasks.toDumpString()}")
             pw.println("${innerPrefix}visibleTasks=${data.visibleTasks.toDumpString()}")
-            pw.println("${innerPrefix}stashed=${data.stashed}")
         }
     }
 
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
index b0d5923..b2bdbfe 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
@@ -240,34 +240,6 @@
         }
     }
 
-    /**
-     * Stash desktop tasks on display with id [displayId].
-     *
-     * When desktop tasks are stashed, launcher home screen icons are fully visible. New apps
-     * launched in this state will be added to the desktop. Existing desktop tasks will be brought
-     * back to front during the launch.
-     */
-    fun stashDesktopApps(displayId: Int) {
-        if (DesktopModeStatus.isStashingEnabled()) {
-            KtProtoLog.v(WM_SHELL_DESKTOP_MODE, "DesktopTasksController: stashDesktopApps")
-            desktopModeTaskRepository.setStashed(displayId, true)
-        }
-    }
-
-    /**
-     * Clear the stashed state for the given display
-     */
-    fun hideStashedDesktopApps(displayId: Int) {
-        if (DesktopModeStatus.isStashingEnabled()) {
-            KtProtoLog.v(
-                    WM_SHELL_DESKTOP_MODE,
-                    "DesktopTasksController: hideStashedApps displayId=%d",
-                    displayId
-            )
-            desktopModeTaskRepository.setStashed(displayId, false)
-        }
-    }
-
     /** Get number of tasks that are marked as visible */
     fun getVisibleTaskCount(displayId: Int): Int {
         return desktopModeTaskRepository.getVisibleTaskCount(displayId)
@@ -871,8 +843,6 @@
         val result = triggerTask?.let { task ->
             when {
                 request.type == TRANSIT_TO_BACK -> handleBackNavigation(task)
-                // If display has tasks stashed, handle as stashed launch
-                task.isStashed -> handleStashedTaskLaunch(task, transition)
                 // Check if the task has a top transparent activity
                 shouldLaunchAsModal(task) -> handleTransparentTaskLaunch(task)
                 // Check if fullscreen task should be updated
@@ -911,12 +881,8 @@
                 .forEach { finishTransaction.setCornerRadius(it.leash, cornerRadius) }
     }
 
-    private val TaskInfo.isStashed: Boolean
-        get() = desktopModeTaskRepository.isStashed(displayId)
-
-    private fun shouldLaunchAsModal(task: TaskInfo): Boolean {
-        return Flags.enableDesktopWindowingModalsPolicy() && isSingleTopActivityTranslucent(task)
-    }
+    private fun shouldLaunchAsModal(task: TaskInfo) =
+        Flags.enableDesktopWindowingModalsPolicy() && isSingleTopActivityTranslucent(task)
 
     private fun shouldRemoveWallpaper(request: TransitionRequestInfo): Boolean {
         return Flags.enableDesktopWindowingWallpaperActivity() &&
@@ -976,24 +942,6 @@
         return null
     }
 
-    private fun handleStashedTaskLaunch(
-            task: RunningTaskInfo,
-            transition: IBinder
-    ): WindowContainerTransaction {
-        KtProtoLog.d(
-                WM_SHELL_DESKTOP_MODE,
-                "DesktopTasksController: launch apps with stashed on transition taskId=%d",
-                task.taskId
-        )
-        val wct = WindowContainerTransaction()
-        val taskToMinimize =
-                bringDesktopAppsToFrontBeforeShowingNewTask(task.displayId, wct, task.taskId)
-        addMoveToDesktopChanges(wct, task)
-        desktopModeTaskRepository.setStashed(task.displayId, false)
-        addPendingMinimizeTransition(transition, taskToMinimize)
-        return wct
-    }
-
     // Always launch transparent tasks in fullscreen.
     private fun handleTransparentTaskLaunch(task: RunningTaskInfo): WindowContainerTransaction? {
         // Already fullscreen, no-op.
@@ -1467,20 +1415,6 @@
             ) { c -> c.showDesktopApps(displayId, remoteTransition) }
         }
 
-        override fun stashDesktopApps(displayId: Int) {
-            ExecutorUtils.executeRemoteCallWithTaskPermission(
-                    controller,
-                    "stashDesktopApps"
-            ) { c -> c.stashDesktopApps(displayId) }
-        }
-
-        override fun hideStashedDesktopApps(displayId: Int) {
-            ExecutorUtils.executeRemoteCallWithTaskPermission(
-                    controller,
-                    "hideStashedDesktopApps"
-            ) { c -> c.hideStashedDesktopApps(displayId) }
-        }
-
         override fun showDesktopApp(taskId: Int) {
             ExecutorUtils.executeRemoteCallWithTaskPermission(
                     controller,
@@ -1488,6 +1422,20 @@
             ) { c -> c.moveTaskToFront(taskId) }
         }
 
+        override fun stashDesktopApps(displayId: Int) {
+            KtProtoLog.w(
+                WM_SHELL_DESKTOP_MODE,
+                "IDesktopModeImpl: stashDesktopApps is deprecated"
+            )
+        }
+
+        override fun hideStashedDesktopApps(displayId: Int) {
+            KtProtoLog.w(
+                WM_SHELL_DESKTOP_MODE,
+                "IDesktopModeImpl: hideStashedDesktopApps is deprecated"
+            )
+        }
+
         override fun getVisibleTaskCount(displayId: Int): Int {
             val result = IntArray(1)
             ExecutorUtils.executeRemoteCallWithTaskPermission(
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopMode.aidl b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopMode.aidl
index fa43522..c36f8de 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopMode.aidl
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopMode.aidl
@@ -28,10 +28,10 @@
     /** Show apps on the desktop on the given display */
     void showDesktopApps(int displayId, in RemoteTransition remoteTransition);
 
-    /** Stash apps on the desktop to allow launching another app from home screen */
+    /** @deprecated use {@link #showDesktopApps} instead. */
     void stashDesktopApps(int displayId);
 
-    /** Hide apps that may be stashed */
+    /** @deprecated this is no longer supported. */
     void hideStashedDesktopApps(int displayId);
 
     /** Bring task with the given id to front */
diff --git a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepositoryTest.kt b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepositoryTest.kt
index dca7be1..8f59f30 100644
--- a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepositoryTest.kt
+++ b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopModeTaskRepositoryTest.kt
@@ -182,18 +182,6 @@
     }
 
     @Test
-    fun addListener_notifiesStashed() {
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        val listener = TestVisibilityListener()
-        val executor = TestShellExecutor()
-        repo.addVisibleTasksListener(listener, executor)
-        executor.flushAll()
-
-        assertThat(listener.stashedOnDefaultDisplay).isTrue()
-        assertThat(listener.stashedChangesOnDefaultDisplay).isEqualTo(1)
-    }
-
-    @Test
     fun addListener_tasksOnDifferentDisplay_doesNotNotify() {
         repo.updateVisibleFreeformTasks(SECOND_DISPLAY, taskId = 1, visible = true)
         val listener = TestVisibilityListener()
@@ -400,65 +388,6 @@
     }
 
     @Test
-    fun setStashed_stateIsUpdatedForTheDisplay() {
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        assertThat(repo.isStashed(DEFAULT_DISPLAY)).isTrue()
-        assertThat(repo.isStashed(SECOND_DISPLAY)).isFalse()
-
-        repo.setStashed(DEFAULT_DISPLAY, false)
-        assertThat(repo.isStashed(DEFAULT_DISPLAY)).isFalse()
-    }
-
-    @Test
-    fun setStashed_notifyListener() {
-        val listener = TestVisibilityListener()
-        val executor = TestShellExecutor()
-        repo.addVisibleTasksListener(listener, executor)
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        executor.flushAll()
-        assertThat(listener.stashedOnDefaultDisplay).isTrue()
-        assertThat(listener.stashedChangesOnDefaultDisplay).isEqualTo(1)
-
-        repo.setStashed(DEFAULT_DISPLAY, false)
-        executor.flushAll()
-        assertThat(listener.stashedOnDefaultDisplay).isFalse()
-        assertThat(listener.stashedChangesOnDefaultDisplay).isEqualTo(2)
-    }
-
-    @Test
-    fun setStashed_secondCallDoesNotNotify() {
-        val listener = TestVisibilityListener()
-        val executor = TestShellExecutor()
-        repo.addVisibleTasksListener(listener, executor)
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        executor.flushAll()
-        assertThat(listener.stashedChangesOnDefaultDisplay).isEqualTo(1)
-    }
-
-    @Test
-    fun setStashed_tracksPerDisplay() {
-        val listener = TestVisibilityListener()
-        val executor = TestShellExecutor()
-        repo.addVisibleTasksListener(listener, executor)
-
-        repo.setStashed(DEFAULT_DISPLAY, true)
-        executor.flushAll()
-        assertThat(listener.stashedOnDefaultDisplay).isTrue()
-        assertThat(listener.stashedOnSecondaryDisplay).isFalse()
-
-        repo.setStashed(SECOND_DISPLAY, true)
-        executor.flushAll()
-        assertThat(listener.stashedOnDefaultDisplay).isTrue()
-        assertThat(listener.stashedOnSecondaryDisplay).isTrue()
-
-        repo.setStashed(DEFAULT_DISPLAY, false)
-        executor.flushAll()
-        assertThat(listener.stashedOnDefaultDisplay).isFalse()
-        assertThat(listener.stashedOnSecondaryDisplay).isTrue()
-    }
-
-    @Test
     fun removeFreeformTask_removesTaskBoundsBeforeMaximize() {
         val taskId = 1
         repo.saveBoundsBeforeMaximize(taskId, Rect(0, 0, 200, 200))
@@ -598,12 +527,6 @@
         var visibleChangesOnDefaultDisplay = 0
         var visibleChangesOnSecondaryDisplay = 0
 
-        var stashedOnDefaultDisplay = false
-        var stashedOnSecondaryDisplay = false
-
-        var stashedChangesOnDefaultDisplay = 0
-        var stashedChangesOnSecondaryDisplay = 0
-
         override fun onTasksVisibilityChanged(displayId: Int, visibleTasksCount: Int) {
             when (displayId) {
                 DEFAULT_DISPLAY -> {
@@ -617,20 +540,6 @@
                 else -> fail("Visible task listener received unexpected display id: $displayId")
             }
         }
-
-        override fun onStashedChanged(displayId: Int, stashed: Boolean) {
-            when (displayId) {
-                DEFAULT_DISPLAY -> {
-                    stashedOnDefaultDisplay = stashed
-                    stashedChangesOnDefaultDisplay++
-                }
-                SECOND_DISPLAY -> {
-                    stashedOnSecondaryDisplay = stashed
-                    stashedChangesOnDefaultDisplay++
-                }
-                else -> fail("Visible task listener received unexpected display id: $displayId")
-            }
-        }
     }
 
     companion object {
diff --git a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
index 3f76c4f..7e55628 100644
--- a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
+++ b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
@@ -1044,29 +1044,6 @@
     }
 
     @Test
-    @DisableFlags(Flags.FLAG_ENABLE_DESKTOP_WINDOWING_WALLPAPER_ACTIVITY)
-    fun handleRequest_fullscreenTask_desktopStashed_returnWCTWithAllAppsBroughtToFront() {
-        assumeTrue(ENABLE_SHELL_TRANSITIONS)
-        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
-
-        val stashedFreeformTask = setUpFreeformTask(DEFAULT_DISPLAY)
-        markTaskHidden(stashedFreeformTask)
-
-        val fullscreenTask = createFullscreenTask(DEFAULT_DISPLAY)
-
-        controller.stashDesktopApps(DEFAULT_DISPLAY)
-
-        val result = controller.handleRequest(Binder(), createTransition(fullscreenTask))
-        assertThat(result).isNotNull()
-        result!!.assertReorderSequence(stashedFreeformTask, fullscreenTask)
-        assertThat(result.changes[fullscreenTask.token.asBinder()]?.windowingMode)
-                .isEqualTo(WINDOWING_MODE_FREEFORM)
-
-        // Stashed state should be cleared
-        assertThat(desktopModeTaskRepository.isStashed(DEFAULT_DISPLAY)).isFalse()
-    }
-
-    @Test
     fun handleRequest_freeformTask_freeformVisible_returnNull() {
         assumeTrue(ENABLE_SHELL_TRANSITIONS)
 
@@ -1133,27 +1110,6 @@
     }
 
     @Test
-    @DisableFlags(Flags.FLAG_ENABLE_DESKTOP_WINDOWING_WALLPAPER_ACTIVITY)
-    fun handleRequest_freeformTask_desktopStashed_returnWCTWithAllAppsBroughtToFront() {
-        assumeTrue(ENABLE_SHELL_TRANSITIONS)
-        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
-
-        val stashedFreeformTask = setUpFreeformTask(DEFAULT_DISPLAY)
-        markTaskHidden(stashedFreeformTask)
-
-        val freeformTask = createFreeformTask(DEFAULT_DISPLAY)
-
-        controller.stashDesktopApps(DEFAULT_DISPLAY)
-
-        val result = controller.handleRequest(Binder(), createTransition(freeformTask))
-        assertThat(result).isNotNull()
-        result?.assertReorderSequence(stashedFreeformTask, freeformTask)
-
-        // Stashed state should be cleared
-        assertThat(desktopModeTaskRepository.isStashed(DEFAULT_DISPLAY)).isFalse()
-    }
-
-    @Test
     fun handleRequest_notOpenOrToFrontTransition_returnNull() {
         assumeTrue(ENABLE_SHELL_TRANSITIONS)
 
@@ -1269,29 +1225,6 @@
     }
 
     @Test
-    fun stashDesktopApps_stateUpdates() {
-        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
-
-        controller.stashDesktopApps(DEFAULT_DISPLAY)
-
-        assertThat(desktopModeTaskRepository.isStashed(DEFAULT_DISPLAY)).isTrue()
-        assertThat(desktopModeTaskRepository.isStashed(SECOND_DISPLAY)).isFalse()
-    }
-
-    @Test
-    fun hideStashedDesktopApps_stateUpdates() {
-        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
-
-        desktopModeTaskRepository.setStashed(DEFAULT_DISPLAY, true)
-        desktopModeTaskRepository.setStashed(SECOND_DISPLAY, true)
-        controller.hideStashedDesktopApps(DEFAULT_DISPLAY)
-
-        assertThat(desktopModeTaskRepository.isStashed(DEFAULT_DISPLAY)).isFalse()
-        // Check that second display is not affected
-        assertThat(desktopModeTaskRepository.isStashed(SECOND_DISPLAY)).isTrue()
-    }
-
-    @Test
     fun desktopTasksVisibilityChange_visible_setLaunchAdjacentDisabled() {
         val task = setUpFreeformTask()
         clearInvocations(launchAdjacentController)