From 579eb8936257bca0a231c7f82bb8f6d408f76492 Mon Sep 17 00:00:00 2001
From: Evan Rosky <erosky@google.com>
Date: Tue, 17 May 2022 17:37:55 -0700
Subject: [PATCH] Detect Remove-pip transaction to properly close
 multi-activity pips

Multi-activity pip converts setWindowingMode(UNDEFINED) into a
"reparent pip activity + move-to-front" when expanding pip. Shell
doesn't know whether a pip is multi-activity or not, so it just
makes a WCT with setWindowingMode(UNDEFINED) AND reorder-to-back.
The problem is that setWindowingMode happens first which triggers
the "merge + move-to-front" logic -- the reorder command was
for the unmerged task so it just gets ignored.

This CL basically checks if the WCT also has a move-to-back in
addition to setMode(UNDEFINED) and, if so, uses the "workaround"
found in removePinnedRootTaskInSurfaceTransaction to prevent
setWindowingMode(UNDEFINED) from doing the wrong thing: it sets
FORCE_HIDDEN_FOR_PINNED_TASK.

Bug: 232954259
Test: open multi-activity pip (eg. ApiDemos). Go to pip. close it
      via the X button.
Change-Id: Iaafbc1c930eb1bcfb427533ae28ef9a823d6b9c6
---
 .../server/wm/WindowOrganizerController.java  | 29 +++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/services/core/java/com/android/server/wm/WindowOrganizerController.java b/services/core/java/com/android/server/wm/WindowOrganizerController.java
index 59a393ad40d6a..128b3292983e6 100644
--- a/services/core/java/com/android/server/wm/WindowOrganizerController.java
+++ b/services/core/java/com/android/server/wm/WindowOrganizerController.java
@@ -18,6 +18,7 @@ package com.android.server.wm;
 
 import static android.Manifest.permission.START_TASKS_FROM_RECENTS;
 import static android.app.ActivityManager.isStartResultSuccessful;
+import static android.app.WindowConfiguration.WINDOWING_MODE_UNDEFINED;
 import static android.view.Display.DEFAULT_DISPLAY;
 import static android.window.WindowContainerTransaction.HierarchyOp.HIERARCHY_OP_TYPE_ADD_RECT_INSETS_PROVIDER;
 import static android.window.WindowContainerTransaction.HierarchyOp.HIERARCHY_OP_TYPE_CHILDREN_TASKS_REPARENT;
@@ -42,6 +43,7 @@ import static android.window.WindowContainerTransaction.HierarchyOp.HIERARCHY_OP
 import static com.android.internal.protolog.ProtoLogGroup.WM_DEBUG_WINDOW_ORGANIZER;
 import static com.android.server.wm.ActivityTaskManagerService.LAYOUT_REASON_CONFIG_CHANGED;
 import static com.android.server.wm.ActivityTaskSupervisor.PRESERVE_WINDOWS;
+import static com.android.server.wm.Task.FLAG_FORCE_HIDDEN_FOR_PINNED_TASK;
 import static com.android.server.wm.Task.FLAG_FORCE_HIDDEN_FOR_TASK_ORG;
 import static com.android.server.wm.WindowContainer.POSITION_BOTTOM;
 import static com.android.server.wm.WindowContainer.POSITION_TOP;
@@ -395,6 +397,8 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
                     effects |= TRANSACT_EFFECTS_LIFECYCLE;
                 }
             }
+            final List<WindowContainerTransaction.HierarchyOp> hops = t.getHierarchyOps();
+            final int hopSize = hops.size();
             ArraySet<WindowContainer> haveConfigChanges = new ArraySet<>();
             Iterator<Map.Entry<IBinder, WindowContainerTransaction.Change>> entries =
                     t.getChanges().entrySet().iterator();
@@ -422,10 +426,33 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
                         transition.setCanPipOnFinish(false /* canPipOnFinish */);
                     }
                 }
+                // A bit hacky, but we need to detect "remove PiP" so that we can "wrap" the
+                // setWindowingMode call in force-hidden.
+                boolean forceHiddenForPip = false;
+                if (wc.asTask() != null && wc.inPinnedWindowingMode()
+                        && entry.getValue().getWindowingMode() == WINDOWING_MODE_UNDEFINED) {
+                    // We are in pip and going to undefined. Now search hierarchy ops to determine
+                    // whether we are removing pip or expanding pip.
+                    for (int i = 0; i < hopSize; ++i) {
+                        final WindowContainerTransaction.HierarchyOp hop = hops.get(i);
+                        if (hop.getType() != HIERARCHY_OP_TYPE_REORDER) continue;
+                        final WindowContainer hopWc = WindowContainer.fromBinder(
+                                hop.getContainer());
+                        if (!wc.equals(hopWc)) continue;
+                        forceHiddenForPip = !hop.getToTop();
+                    }
+                }
+                if (forceHiddenForPip) {
+                    wc.asTask().setForceHidden(FLAG_FORCE_HIDDEN_FOR_PINNED_TASK, true /* set */);
+                }
 
                 int containerEffect = applyWindowContainerChange(wc, entry.getValue());
                 effects |= containerEffect;
 
+                if (forceHiddenForPip) {
+                    wc.asTask().setForceHidden(FLAG_FORCE_HIDDEN_FOR_PINNED_TASK, false /* set */);
+                }
+
                 // Lifecycle changes will trigger ensureConfig for everything.
                 if ((effects & TRANSACT_EFFECTS_LIFECYCLE) == 0
                         && (containerEffect & TRANSACT_EFFECTS_CLIENT_CONFIG) != 0) {
@@ -433,8 +460,6 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
                 }
             }
             // Hierarchy changes
-            final List<WindowContainerTransaction.HierarchyOp> hops = t.getHierarchyOps();
-            final int hopSize = hops.size();
             if (hopSize > 0) {
                 final boolean isInLockTaskMode = mService.isInLockTaskMode();
                 for (int i = 0; i < hopSize; ++i) {