From 910089a8abead84676944bf0fc17395e08740977 Mon Sep 17 00:00:00 2001
From: Evan Rosky <erosky@google.com>
Date: Fri, 12 Jun 2020 14:58:41 -0700
Subject: [PATCH] Track recents like home for times when it is separated

when using 3p launchers, recents is a separate stack. As
such we need to make sure that the recents root is provided
when asked for just like home is.

Bug: 158851728
Test: Using 3p launcher in split-secondary, open recents
Change-Id: I90dc6e75a718aa142c870b87bd93081e259acdea
---
 .../android/server/wm/TaskDisplayArea.java    | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/services/core/java/com/android/server/wm/TaskDisplayArea.java b/services/core/java/com/android/server/wm/TaskDisplayArea.java
index 102c2a6364f4e..10f2aabe1ddee 100644
--- a/services/core/java/com/android/server/wm/TaskDisplayArea.java
+++ b/services/core/java/com/android/server/wm/TaskDisplayArea.java
@@ -17,6 +17,7 @@
 package com.android.server.wm;
 
 import static android.app.WindowConfiguration.ACTIVITY_TYPE_HOME;
+import static android.app.WindowConfiguration.ACTIVITY_TYPE_RECENTS;
 import static android.app.WindowConfiguration.ACTIVITY_TYPE_STANDARD;
 import static android.app.WindowConfiguration.ACTIVITY_TYPE_UNDEFINED;
 import static android.app.WindowConfiguration.WINDOWING_MODE_FREEFORM;
@@ -99,6 +100,9 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
     private ActivityStack mRootPinnedTask;
     private ActivityStack mRootSplitScreenPrimaryTask;
 
+    // TODO(b/159029784): Remove when getStack() behavior is cleaned-up
+    private ActivityStack mRootRecentsTask;
+
     private final ArrayList<ActivityStack> mTmpAlwaysOnTopStacks = new ArrayList<>();
     private final ArrayList<ActivityStack> mTmpNormalStacks = new ArrayList<>();
     private final ArrayList<ActivityStack> mTmpHomeStacks = new ArrayList<>();
@@ -163,6 +167,8 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
     ActivityStack getStack(int windowingMode, int activityType) {
         if (activityType == ACTIVITY_TYPE_HOME) {
             return mRootHomeTask;
+        } else if (activityType == ACTIVITY_TYPE_RECENTS) {
+            return mRootRecentsTask;
         }
         if (windowingMode == WINDOWING_MODE_PINNED) {
             return mRootPinnedTask;
@@ -199,6 +205,10 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
         return mRootHomeTask;
     }
 
+    @Nullable ActivityStack getRootRecentsTask() {
+        return mRootRecentsTask;
+    }
+
     ActivityStack getRootPinnedTask() {
         return mRootPinnedTask;
     }
@@ -237,6 +247,16 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
             } else {
                 mRootHomeTask = stack;
             }
+        } else if (stack.isActivityTypeRecents()) {
+            if (mRootRecentsTask != null) {
+                if (!stack.isDescendantOf(mRootRecentsTask)) {
+                    throw new IllegalArgumentException("addStackReferenceIfNeeded: recents stack="
+                            + mRootRecentsTask + " already exist on display=" + this
+                            + " stack=" + stack);
+                }
+            } else {
+                mRootRecentsTask = stack;
+            }
         }
 
         if (!stack.isRootTask()) {
@@ -264,6 +284,8 @@ final class TaskDisplayArea extends DisplayArea<ActivityStack> {
     void removeStackReferenceIfNeeded(ActivityStack stack) {
         if (stack == mRootHomeTask) {
             mRootHomeTask = null;
+        } else if (stack == mRootRecentsTask) {
+            mRootRecentsTask = null;
         } else if (stack == mRootPinnedTask) {
             mRootPinnedTask = null;
         } else if (stack == mRootSplitScreenPrimaryTask) {