Fix accessiblity CTS tests (framework).

1. An external contribution changed the ordering of views for
   accessibility. While it attempted to fix a platform issue
   for a comparator breaking transitivity, it changed the way
   we order views and results in very unnatural accessibility
   traversal order. It also broke CTS tets. This change tweaks
   the comparator which fixes the tests and improves traversal
   order.

2. If there is at least one accessibility service which cares
   about windows we register a callback in the window manager
   for window change notifications. We are updating the window
   list on this callback. There was a case where if the service
   requests window updates and immediately asks for the windows
   it gets none as we have not received a callback from the
   window manager yet. Now this call returns after we get the
   callback in a timed fashion. This is consistent with how the
   other introspection APIs work.

3. Window info objects are cached in the accessibility service
   process. When putting them in the cache a cloning call was
   missing resulting in some cases of clobbering windows given
   to the client. For example, we get some windows, cache them,
   and return these windows to the client. Now a call to clear
   the cache arrives while the user processes the windows and
   the client windows get clobbered.

4. Added API for checking if a window has accessiblity focus
   to be consistent to the API we have to check whether this
   window has input focus.

5. Removed some obsolete code.

bug:16402352

Change-Id: Ided6da4a82cc0fc703008c58a2dff0119a3ff317

5 files changed, 132 insertions, 52 deletions

diff --git a/api/current.txt b/api/current.txt
index eacc45261261..7665f43476d4 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -35771,6 +35771,7 @@ package android.view.accessibility {
     method public android.view.accessibility.AccessibilityWindowInfo getParent();
     method public android.view.accessibility.AccessibilityNodeInfo getRoot();
     method public int getType();
+    method public boolean isAccessibilityFocused();
     method public boolean isActive();
     method public boolean isFocused();
     method public static android.view.accessibility.AccessibilityWindowInfo obtain();
diff --git a/core/java/android/view/ViewGroup.java b/core/java/android/view/ViewGroup.java
index 19dd5837fe42..f54f8249bbda 100644
--- a/core/java/android/view/ViewGroup.java
+++ b/core/java/android/view/ViewGroup.java
@@ -7021,27 +7021,23 @@ public abstract class ViewGroup extends View implements ViewParent, ViewManager
             if (another == null) {
                 return 1;
             }
-            if (getClass() != another.getClass()) {
-                return 1;
-            }
-            final int topDiference = mLocation.top - another.mLocation.top;
-            if (topDiference != 0) {
-                return topDiference;
-            }
-            // LTR
+            // We are ordering left-to-right, top-to-bottom.
             if (mLayoutDirection == LAYOUT_DIRECTION_LTR) {
                 final int leftDifference = mLocation.left - another.mLocation.left;
-                // First more to the left than second.
                 if (leftDifference != 0) {
                     return leftDifference;
                 }
             } else { // RTL
                 final int rightDifference = mLocation.right - another.mLocation.right;
-                // First more to the right than second.
                 if (rightDifference != 0) {
                     return -rightDifference;
                 }
             }
+            // We are ordering left-to-right, top-to-bottom.
+            final int topDifference = mLocation.top - another.mLocation.top;
+            if (topDifference != 0) {
+                return topDifference;
+            }
             // Break tie by height.
             final int heightDiference = mLocation.height() - another.mLocation.height();
             if (heightDiference != 0) {
diff --git a/core/java/android/view/accessibility/AccessibilityCache.java b/core/java/android/view/accessibility/AccessibilityCache.java
index ca6437a4d31c..ead757eb9a7d 100644
--- a/core/java/android/view/accessibility/AccessibilityCache.java
+++ b/core/java/android/view/accessibility/AccessibilityCache.java
@@ -54,7 +54,12 @@ final class AccessibilityCache {
             if (DEBUG) {
                 Log.i(LOG_TAG, "Caching window: " + window.getId());
             }
-            mWindowCache.put(window.getId(), window);
+            final int windowId = window.getId();
+            AccessibilityWindowInfo oldWindow = mWindowCache.get(windowId);
+            if (oldWindow != null) {
+                oldWindow.recycle();
+            }
+            mWindowCache.put(windowId, AccessibilityWindowInfo.obtain(window));
         }
     }
 
@@ -183,14 +188,13 @@ final class AccessibilityCache {
                     sortedWindows.put(window.getLayer(), window);
                 }
 
-                List<AccessibilityWindowInfo> windows = new ArrayList<>();
+                List<AccessibilityWindowInfo> windows = new ArrayList<>(windowCount);
                 for (int i = windowCount - 1; i >= 0; i--) {
                     AccessibilityWindowInfo window = sortedWindows.valueAt(i);
                     windows.add(AccessibilityWindowInfo.obtain(window));
+                    sortedWindows.removeAt(i);
                 }
 
-                sortedWindows.clear();
-
                 return windows;
             }
             return null;
diff --git a/core/java/android/view/accessibility/AccessibilityWindowInfo.java b/core/java/android/view/accessibility/AccessibilityWindowInfo.java
index 80b5c5071c3a..ad55f5f2a097 100644
--- a/core/java/android/view/accessibility/AccessibilityWindowInfo.java
+++ b/core/java/android/view/accessibility/AccessibilityWindowInfo.java
@@ -55,6 +55,7 @@ public final class AccessibilityWindowInfo implements Parcelable {
 
     private static final int BOOLEAN_PROPERTY_ACTIVE = 1 << 0;
     private static final int BOOLEAN_PROPERTY_FOCUSED = 1 << 1;
+    private static final int BOOLEAN_PROPERTY_ACCESSIBLITY_FOCUSED = 1 << 2;
 
     // Housekeeping.
     private static final int MAX_POOL_SIZE = 10;
@@ -258,6 +259,26 @@ public final class AccessibilityWindowInfo implements Parcelable {
     }
 
     /**
+     * Gets if this window has accessibility focus.
+     *
+     * @return Whether has accessibility focus.
+     */
+    public boolean isAccessibilityFocused() {
+        return getBooleanProperty(BOOLEAN_PROPERTY_ACCESSIBLITY_FOCUSED);
+    }
+
+    /**
+     * Sets if this window has accessibility focus.
+     *
+     * @param Whether has accessibility focus.
+     *
+     * @hide
+     */
+    public void setAccessibilityFocused(boolean focused) {
+        setBooleanProperty(BOOLEAN_PROPERTY_ACCESSIBLITY_FOCUSED, focused);
+    }
+
+    /**
      * Gets the number of child windows.
      *
      * @return The child count.
diff --git a/services/accessibility/java/com/android/server/accessibility/AccessibilityManagerService.java b/services/accessibility/java/com/android/server/accessibility/AccessibilityManagerService.java
index b1f19540060c..4e2f52c5e5b7 100644
--- a/services/accessibility/java/com/android/server/accessibility/AccessibilityManagerService.java
+++ b/services/accessibility/java/com/android/server/accessibility/AccessibilityManagerService.java
@@ -124,6 +124,8 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
     //       when that accessibility services are bound.
     private static final int WAIT_FOR_USER_STATE_FULLY_INITIALIZED_MILLIS = 3000;
 
+    private static final int WAIT_WINDOWS_TIMEOUT_MILLIS = 5000;
+
     private static final String FUNCTION_REGISTER_UI_TEST_AUTOMATION_SERVICE =
         "registerUiTestAutomationService";
 
@@ -1367,6 +1369,8 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
         if (mWindowsForAccessibilityCallback != null) {
             mWindowsForAccessibilityCallback = null;
             mWindowManagerService.setWindowsForAccessibilityCallback(null);
+            // Drop all windows we know about.
+            mSecurityPolicy.clearWindowsLocked();
         }
     }
 
@@ -1631,16 +1635,18 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                 pw.println("}]");
                 pw.println();
             }
-            final int windowCount = mSecurityPolicy.mWindows.size();
-            for (int j = 0; j < windowCount; j++) {
-                if (j > 0) {
-                    pw.append(',');
-                    pw.println();
+            if (mSecurityPolicy.mWindows != null) {
+                final int windowCount = mSecurityPolicy.mWindows.size();
+                for (int j = 0; j < windowCount; j++) {
+                    if (j > 0) {
+                        pw.append(',');
+                        pw.println();
+                    }
+                    pw.append("Window[");
+                    AccessibilityWindowInfo window = mSecurityPolicy.mWindows.get(j);
+                    pw.append(window.toString());
+                    pw.append(']');
                 }
-                pw.append("Window[");
-                AccessibilityWindowInfo window = mSecurityPolicy.mWindows.get(j);
-                pw.append(window.toString());
-                pw.append(']');
             }
         }
     }
@@ -1821,6 +1827,39 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
         return -1;
     }
 
+    private void ensureWindowsAvailableTimed() {
+        synchronized (mLock) {
+            if (mSecurityPolicy.mWindows != null) {
+                return;
+            }
+            // If we have no registered callback, update the state we
+            // we may have to register one but it didn't happen yet.
+            if (mWindowsForAccessibilityCallback == null) {
+                UserState userState = getCurrentUserStateLocked();
+                onUserStateChangedLocked(userState);
+            }
+            // We have no windows but do not care about them, done.
+            if (mWindowsForAccessibilityCallback == null) {
+                return;
+            }
+
+            // Wait for the windows with a timeout.
+            final long startMillis = SystemClock.uptimeMillis();
+            while (mSecurityPolicy.mWindows == null) {
+                final long elapsedMillis = SystemClock.uptimeMillis() - startMillis;
+                final long remainMillis = WAIT_WINDOWS_TIMEOUT_MILLIS - elapsedMillis;
+                if (remainMillis <= 0) {
+                    return;
+                }
+                try {
+                    mLock.wait(remainMillis);
+                } catch (InterruptedException ie) {
+                    /* ignore */
+                }
+            }
+        }
+    }
+
     /**
      * This class represents an accessibility service. It stores all per service
      * data required for the service management, provides API for starting/stopping the
@@ -1876,9 +1915,6 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
 
         final KeyEventDispatcher mKeyEventDispatcher = new KeyEventDispatcher();
 
-        final SparseArray<AccessibilityWindowInfo> mIntrospectedWindows =
-                new SparseArray<>();
-
         boolean mWasConnectedAndDied;
 
         // Handler only for dispatching accessibility events since we use event
@@ -1946,10 +1982,6 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                     & AccessibilityServiceInfo.FLAG_REQUEST_FILTER_KEY_EVENTS) != 0;
             mRetrieveInteractiveWindows = (info.flags
                     & AccessibilityServiceInfo.FLAG_RETRIEVE_INTERACTIVE_WINDOWS) != 0;
-
-            if (!mRetrieveInteractiveWindows) {
-                clearIntrospectedWindows();
-            }
         }
 
         /**
@@ -2065,6 +2097,7 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
 
         @Override
         public List<AccessibilityWindowInfo> getWindows() {
+            ensureWindowsAvailableTimed();
             synchronized (mLock) {
                 // We treat calls from a profile as if made by its perent as profiles
                 // share the accessibility state of the parent. The call below
@@ -2087,7 +2120,6 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                     AccessibilityWindowInfo windowClone =
                             AccessibilityWindowInfo.obtain(window);
                     windowClone.setConnectionId(mId);
-                    mIntrospectedWindows.put(window.getId(), windowClone);
                     windows.add(windowClone);
                 }
                 return windows;
@@ -2096,6 +2128,7 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
 
         @Override
         public AccessibilityWindowInfo getWindow(int windowId) {
+            ensureWindowsAvailableTimed();
             synchronized (mLock) {
                 // We treat calls from a profile as if made by its parent as profiles
                 // share the accessibility state of the parent. The call below
@@ -2115,7 +2148,6 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                 if (window != null) {
                     AccessibilityWindowInfo windowClone = AccessibilityWindowInfo.obtain(window);
                     windowClone.setConnectionId(mId);
-                    mIntrospectedWindows.put(windowId, windowClone);
                     return windowClone;
                 }
                 return null;
@@ -2607,19 +2639,10 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
         }
 
         public void notifyClearAccessibilityNodeInfoCache() {
-            clearIntrospectedWindows();
             mInvocationHandler.sendEmptyMessage(
                     InvocationHandler.MSG_CLEAR_ACCESSIBILITY_CACHE);
         }
 
-        private void clearIntrospectedWindows() {
-            final int windowCount = mIntrospectedWindows.size();
-            for (int i = windowCount - 1; i >= 0; i--) {
-                mIntrospectedWindows.valueAt(i).recycle();
-                mIntrospectedWindows.removeAt(i);
-            }
-        }
-
         private void notifyGestureInternal(int gestureId) {
             final IAccessibilityServiceClient listener;
             synchronized (mLock) {
@@ -2955,6 +2978,9 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
 
                 // Let the policy update the focused and active windows.
                 mSecurityPolicy.updateWindowsLocked(reportedWindows);
+
+                // Someone may be waiting for the windows - advertise it.
+                mLock.notifyAll();
             }
         }
 
@@ -3130,7 +3156,7 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
             | AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUS_CLEARED
             | AccessibilityEvent.TYPE_VIEW_TEXT_TRAVERSED_AT_MOVEMENT_GRANULARITY;
 
-        public final List<AccessibilityWindowInfo> mWindows = new ArrayList<>();
+        public List<AccessibilityWindowInfo> mWindows;
 
         public int mActiveWindowId = INVALID_WINDOW_ID;
         public int mFocusedWindowId = INVALID_WINDOW_ID;
@@ -3185,7 +3211,17 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
             }
         }
 
+        public void clearWindowsLocked() {
+            List<AccessibilityWindowInfo> windows = Collections.emptyList();
+            updateWindowsLocked(windows);
+            mWindows = null;
+        }
+
         public void updateWindowsLocked(List<AccessibilityWindowInfo> windows) {
+            if (mWindows == null) {
+                mWindows = new ArrayList<>();
+            }
+
             final int oldWindowCount = mWindows.size();
             for (int i = oldWindowCount - 1; i >= 0; i--) {
                 mWindows.remove(i).recycle();
@@ -3231,6 +3267,9 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                     if (window.getId() == mActiveWindowId) {
                         window.setActive(true);
                     }
+                    if (window.getId() == mAccessibilityFocusedWindowId) {
+                        window.setAccessibilityFocused(true);
+                    }
                 }
             }
 
@@ -3298,7 +3337,7 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
                         if (mAccessibilityFocusedWindowId != windowId) {
                             mMainHandler.obtainMessage(MainHandler.MSG_CLEAR_ACCESSIBILITY_FOCUS,
                                     mAccessibilityFocusedWindowId, 0).sendToTarget();
-                            mAccessibilityFocusedWindowId = windowId;
+                            mSecurityPolicy.setAccessibilityFocusedWindowLocked(windowId);
                             mAccessibilityFocusNodeId = nodeId;
                         }
                     }
@@ -3354,11 +3393,28 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
         private void setActiveWindowLocked(int windowId) {
             if (mActiveWindowId != windowId) {
                 mActiveWindowId = windowId;
-                final int windowCount = mWindows.size();
-                for (int i = 0; i < windowCount; i++) {
-                    AccessibilityWindowInfo window = mWindows.get(i);
-                    window.setActive(window.getId() == windowId);
+                if (mWindows != null) {
+                    final int windowCount = mWindows.size();
+                    for (int i = 0; i < windowCount; i++) {
+                        AccessibilityWindowInfo window = mWindows.get(i);
+                        window.setActive(window.getId() == windowId);
+                    }
+                }
+                notifyWindowsChanged();
+            }
+        }
+
+        private void setAccessibilityFocusedWindowLocked(int windowId) {
+            if (mAccessibilityFocusedWindowId != windowId) {
+                mAccessibilityFocusedWindowId = windowId;
+                if (mWindows != null) {
+                    final int windowCount = mWindows.size();
+                    for (int i = 0; i < windowCount; i++) {
+                        AccessibilityWindowInfo window = mWindows.get(i);
+                        window.setAccessibilityFocused(window.getId() == windowId);
+                    }
                 }
+
                 notifyWindowsChanged();
             }
         }
@@ -3444,11 +3500,13 @@ public class AccessibilityManagerService extends IAccessibilityManager.Stub {
         }
 
         private AccessibilityWindowInfo findWindowById(int windowId) {
-            final int windowCount = mWindows.size();
-            for (int i = 0; i < windowCount; i++) {
-                AccessibilityWindowInfo window = mWindows.get(i);
-                if (window.getId() == windowId) {
-                    return window;
+            if (mWindows != null) {
+                final int windowCount = mWindows.size();
+                for (int i = 0; i < windowCount; i++) {
+                    AccessibilityWindowInfo window = mWindows.get(i);
+                    if (window.getId() == windowId) {
+                        return window;
+                    }
                 }
             }
             return null;