From 14a345124c4c5c1e8cc0fd82ebfe69bca45926c1 Mon Sep 17 00:00:00 2001
From: Jacky Kao <jackykao@google.com>
Date: Thu, 16 Apr 2020 15:53:49 +0800
Subject: [PATCH] Fix CTS test case failure

android.accessibilityservice.cts.AccessibilityEmbeddedDisplayTest#
testA11yWindowNotifyWhenResizeWindowInActivityViewAfterServiceOffAndOn

Removing the windowsForA11yObserver of embedded displays when
removing the windowsForA11yObserver of its parent display because the
windowsForA11yObserver is the same of them.

Bug: 153342178
Test: a11y CTS & unit tests
Test: atest --iterations 20 AccessibilityEmbeddedDisplayTest

Change-Id: Idd21692cc599b565219e1cd3960d0cee3298e66b
---
 .../server/wm/AccessibilityController.java    | 60 ++++++++++++++++---
 1 file changed, 52 insertions(+), 8 deletions(-)

diff --git a/services/core/java/com/android/server/wm/AccessibilityController.java b/services/core/java/com/android/server/wm/AccessibilityController.java
index 9d630293c82da..785ca908b7033 100644
--- a/services/core/java/com/android/server/wm/AccessibilityController.java
+++ b/services/core/java/com/android/server/wm/AccessibilityController.java
@@ -45,6 +45,7 @@ import android.os.IBinder;
 import android.os.Looper;
 import android.os.Message;
 import android.util.ArraySet;
+import android.util.IntArray;
 import android.util.Slog;
 import android.util.SparseArray;
 import android.util.TypedValue;
@@ -128,14 +129,13 @@ final class AccessibilityController {
      */
     public boolean setWindowsForAccessibilityCallbackLocked(int displayId,
             WindowsForAccessibilityCallback callback) {
-        if (callback != null) {
-            final DisplayContent dc = mService.mRoot.getDisplayContentOrCreate(displayId);
-            if (dc == null) {
-                return false;
-            }
+        final DisplayContent dc = mService.mRoot.getDisplayContentOrCreate(displayId);
+        if (dc == null) {
+            return false;
+        }
 
-            final Display display = dc.getDisplay();
-            if (display.getType() == Display.TYPE_VIRTUAL && dc.getParentWindow() != null) {
+        if (callback != null) {
+            if (isEmbeddedDisplay(dc)) {
                 // If this display is an embedded one, its window observer should have been set from
                 // window manager after setting its parent window. But if its window observer is
                 // empty, that means this mapping didn't be set, and needs to do this again.
@@ -152,13 +152,22 @@ final class AccessibilityController {
             mWindowsForAccessibilityObserver.put(displayId,
                     new WindowsForAccessibilityObserver(mService, displayId, callback));
         } else {
+            if (isEmbeddedDisplay(dc)) {
+                // If this display is an embedded one, its window observer should be removed along
+                // with the window observer of its parent display removed because the window
+                // observer of the embedded display and its parent display is the same, and would
+                // be removed together when stopping the window tracking of its parent display. So
+                // here don't need to do removing window observer of the embedded display again.
+                return true;
+            }
             final WindowsForAccessibilityObserver windowsForA11yObserver =
                     mWindowsForAccessibilityObserver.get(displayId);
-            if  (windowsForA11yObserver == null) {
+            if (windowsForA11yObserver == null) {
                 throw new IllegalStateException(
                         "Windows for accessibility callback of display " + displayId
                                 + " already cleared!");
             }
+            removeObserverOfEmbeddedDisplay(windowsForA11yObserver);
             mWindowsForAccessibilityObserver.remove(displayId);
         }
         return true;
@@ -332,6 +341,7 @@ final class AccessibilityController {
                 mWindowsForAccessibilityObserver.get(parentDisplayId);
 
         if (windowsForA11yObserver != null) {
+            windowsForA11yObserver.addEmbeddedDisplay(embeddedDisplayId);
             // Replaces the observer of embedded display to the one of parent display
             mWindowsForAccessibilityObserver.put(embeddedDisplayId, windowsForA11yObserver);
         }
@@ -352,6 +362,23 @@ final class AccessibilityController {
         }
     }
 
+    private void removeObserverOfEmbeddedDisplay(WindowsForAccessibilityObserver
+            observerOfParentDisplay) {
+        final IntArray embeddedDisplayIdList =
+                observerOfParentDisplay.getAndClearEmbeddedDisplayIdList();
+
+        for (int index = 0; index < embeddedDisplayIdList.size(); index++) {
+            final int embeddedDisplayId = embeddedDisplayIdList.get(index);
+            mWindowsForAccessibilityObserver.remove(embeddedDisplayId);
+        }
+    }
+
+    private static boolean isEmbeddedDisplay(DisplayContent dc) {
+        final Display display = dc.getDisplay();
+
+        return display.getType() == Display.TYPE_VIRTUAL && dc.getParentWindow() != null;
+    }
+
     /**
      * This class encapsulates the functionality related to display magnification.
      */
@@ -1179,6 +1206,8 @@ final class AccessibilityController {
 
         private final long mRecurringAccessibilityEventsIntervalMillis;
 
+        private final IntArray mEmbeddedDisplayIdList = new IntArray(0);
+
         public WindowsForAccessibilityObserver(WindowManagerService windowManagerService,
                 int displayId,
                 WindowsForAccessibilityCallback callback) {
@@ -1203,6 +1232,21 @@ final class AccessibilityController {
             }
         }
 
+        IntArray getAndClearEmbeddedDisplayIdList() {
+            final IntArray returnedArray = new IntArray(mEmbeddedDisplayIdList.size());
+            returnedArray.addAll(mEmbeddedDisplayIdList);
+            mEmbeddedDisplayIdList.clear();
+
+            return returnedArray;
+        }
+
+        void addEmbeddedDisplay(int displayId) {
+            if (displayId == mDisplayId) {
+                return;
+            }
+            mEmbeddedDisplayIdList.add(displayId);
+        }
+
         /**
          * Check if windows have changed, and send them to the accessibility subsystem if they have.
          *