Immediately stop running face auth if the display is OFF

And prevent face auth from running if the display is OFF.

Only prevent running face auth based on the display state
if the feature flag 'flag_stop_face_auth_on_display_off" is
enabled. In general, face auth relies on the "waking up"
and "going to sleep" signals. That said, when the device
starts "waking up", immediately update the allowedDisplayState
to TRUE to pre-emptively prep for the display state changing to
ON, since display state changes do not START face auth again.

Also fixes out of order KeyguardFaceListenModel.

Test: atest KeyguardUpdateMonitortest
Test: manual
Bug: 290077758
Bug: 294221702
Change-Id: Ie68db6a998fdff1c8b2b79d75650f999bcc55c13

packages/SystemUI/res/values/flags.xml

@@ -38,4 +38,6 @@
          protected. -->
     <bool name="flag_battery_shield_icon">false</bool>
 
+    <!-- Whether face auth will immediately stop when the display state is OFF -->
+    <bool name="flag_stop_face_auth_on_display_off">false</bool>
 </resources>

packages/SystemUI/src/com/android/keyguard/FaceAuthReason.kt

@@ -33,6 +33,7 @@ import com.android.keyguard.InternalFaceAuthReasons.AUTH_REQUEST_DURING_CANCELLA
 import com.android.keyguard.InternalFaceAuthReasons.BIOMETRIC_ENABLED
 import com.android.keyguard.InternalFaceAuthReasons.CAMERA_LAUNCHED
 import com.android.keyguard.InternalFaceAuthReasons.DEVICE_WOKEN_UP_ON_REACH_GESTURE
+import com.android.keyguard.InternalFaceAuthReasons.DISPLAY_OFF
 import com.android.keyguard.InternalFaceAuthReasons.DREAM_STARTED
 import com.android.keyguard.InternalFaceAuthReasons.DREAM_STOPPED
 import com.android.keyguard.InternalFaceAuthReasons.ENROLLMENTS_CHANGED
@@ -131,6 +132,7 @@ private object InternalFaceAuthReasons {
     const val NON_STRONG_BIOMETRIC_ALLOWED_CHANGED =
         "Face auth stopped because non strong biometric allowed changed"
     const val POSTURE_CHANGED = "Face auth started/stopped due to device posture changed."
+    const val DISPLAY_OFF = "Face auth stopped due to display state OFF."
 }
 
 /**
@@ -221,7 +223,8 @@ constructor(private val id: Int, val reason: String, var extraInfo: Int = 0) :
     FACE_AUTH_UPDATED_STRONG_AUTH_CHANGED(1255, STRONG_AUTH_ALLOWED_CHANGED),
     @UiEvent(doc = NON_STRONG_BIOMETRIC_ALLOWED_CHANGED)
     FACE_AUTH_NON_STRONG_BIOMETRIC_ALLOWED_CHANGED(1256, NON_STRONG_BIOMETRIC_ALLOWED_CHANGED),
-    @UiEvent(doc = ACCESSIBILITY_ACTION) FACE_AUTH_ACCESSIBILITY_ACTION(1454, ACCESSIBILITY_ACTION);
+    @UiEvent(doc = ACCESSIBILITY_ACTION) FACE_AUTH_ACCESSIBILITY_ACTION(1454, ACCESSIBILITY_ACTION),
+    @UiEvent(doc = DISPLAY_OFF) FACE_AUTH_DISPLAY_OFF(1461, DISPLAY_OFF);
 
     override fun getId(): Int = this.id
 

packages/SystemUI/src/com/android/keyguard/KeyguardFaceListenModel.kt

@@ -27,6 +27,7 @@ data class KeyguardFaceListenModel(
     override var userId: Int = 0,
     override var listening: Boolean = false,
     // keep sorted
+    var allowedDisplayState: Boolean = false,
     var alternateBouncerShowing: Boolean = false,
     var authInterruptActive: Boolean = false,
     var biometricSettingEnabledForUser: Boolean = false,
@@ -57,6 +58,8 @@ data class KeyguardFaceListenModel(
             userId.toString(),
             listening.toString(),
             // keep sorted
+            allowedDisplayState.toString(),
+            alternateBouncerShowing.toString(),
             authInterruptActive.toString(),
             biometricSettingEnabledForUser.toString(),
             bouncerFullyShown.toString(),
@@ -74,7 +77,6 @@ data class KeyguardFaceListenModel(
             supportsDetect.toString(),
             switchingUser.toString(),
             systemUser.toString(),
-            alternateBouncerShowing.toString(),
             udfpsFingerDown.toString(),
             userNotTrustedOrDetectionIsNeeded.toString(),
         )
@@ -96,7 +98,9 @@ data class KeyguardFaceListenModel(
                 userId = model.userId
                 listening = model.listening
                 // keep sorted
+                allowedDisplayState = model.allowedDisplayState
                 alternateBouncerShowing = model.alternateBouncerShowing
+                authInterruptActive = model.authInterruptActive
                 biometricSettingEnabledForUser = model.biometricSettingEnabledForUser
                 bouncerFullyShown = model.bouncerFullyShown
                 faceAndFpNotAuthenticated = model.faceAndFpNotAuthenticated
@@ -105,7 +109,6 @@ data class KeyguardFaceListenModel(
                 faceLockedOut = model.faceLockedOut
                 goingToSleep = model.goingToSleep
                 keyguardAwake = model.keyguardAwake
-                goingToSleep = model.goingToSleep
                 keyguardGoingAway = model.keyguardGoingAway
                 listeningForFaceAssistant = model.listeningForFaceAssistant
                 occludingAppRequestingFaceAuth = model.occludingAppRequestingFaceAuth
@@ -140,6 +143,8 @@ data class KeyguardFaceListenModel(
                 "userId",
                 "listening",
                 // keep sorted
+                "allowedDisplayState",
+                "alternateBouncerShowing",
                 "authInterruptActive",
                 "biometricSettingEnabledForUser",
                 "bouncerFullyShown",
@@ -157,7 +162,6 @@ data class KeyguardFaceListenModel(
                 "supportsDetect",
                 "switchingUser",
                 "systemUser",
-                "udfpsBouncerShowing",
                 "udfpsFingerDown",
                 "userNotTrustedOrDetectionIsNeeded",
             )

packages/SystemUI/src/com/android/keyguard/KeyguardUpdateMonitor.java

@@ -41,6 +41,7 @@ import static com.android.internal.widget.LockPatternUtils.StrongAuthTracker.STR
 import static com.android.internal.widget.LockPatternUtils.StrongAuthTracker.STRONG_AUTH_REQUIRED_AFTER_LOCKOUT;
 import static com.android.internal.widget.LockPatternUtils.StrongAuthTracker.STRONG_AUTH_REQUIRED_AFTER_USER_LOCKDOWN;
 import static com.android.keyguard.FaceAuthReasonKt.apiRequestReasonToUiEvent;
+import static com.android.keyguard.FaceAuthUiEvent.FACE_AUTH_DISPLAY_OFF;
 import static com.android.keyguard.FaceAuthUiEvent.FACE_AUTH_NON_STRONG_BIOMETRIC_ALLOWED_CHANGED;
 import static com.android.keyguard.FaceAuthUiEvent.FACE_AUTH_STOPPED_DREAM_STARTED;
 import static com.android.keyguard.FaceAuthUiEvent.FACE_AUTH_STOPPED_FACE_CANCEL_NOT_RECEIVED;
@@ -135,6 +136,7 @@ import android.telephony.TelephonyManager;
 import android.text.TextUtils;
 import android.util.SparseArray;
 import android.util.SparseBooleanArray;
+import android.view.Display;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -175,6 +177,7 @@ import com.android.systemui.keyguard.shared.model.SysUiFaceAuthenticateOptions;
 import com.android.systemui.log.SessionTracker;
 import com.android.systemui.plugins.WeatherData;
 import com.android.systemui.plugins.statusbar.StatusBarStateController;
+import com.android.systemui.settings.DisplayTracker;
 import com.android.systemui.settings.UserTracker;
 import com.android.systemui.shared.system.TaskStackChangeListener;
 import com.android.systemui.shared.system.TaskStackChangeListeners;
@@ -335,6 +338,25 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
             }
         }
     };
+    private final DisplayTracker.Callback mDisplayCallback = new DisplayTracker.Callback() {
+        @Override
+        public void onDisplayChanged(int displayId) {
+            if (displayId != Display.DEFAULT_DISPLAY) {
+                return;
+            }
+
+            if (mDisplayTracker.getDisplay(mDisplayTracker.getDefaultDisplayId()).getState()
+                    == Display.STATE_OFF) {
+                mAllowedDisplayStateForFaceAuth = false;
+                updateFaceListeningState(
+                        BIOMETRIC_ACTION_STOP,
+                        FACE_AUTH_DISPLAY_OFF
+                );
+            } else {
+                mAllowedDisplayStateForFaceAuth = true;
+            }
+        }
+    };
     private final FaceWakeUpTriggersConfig mFaceWakeUpTriggersConfig;
 
     HashMap<Integer, SimData> mSimDatas = new HashMap<>();
@@ -355,6 +377,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
     private boolean mOccludingAppRequestingFp;
     private boolean mOccludingAppRequestingFace;
     private boolean mSecureCameraLaunched;
+    private boolean mAllowedDisplayStateForFaceAuth = true;
     @VisibleForTesting
     protected boolean mTelephonyCapable;
     private boolean mAllowFingerprintOnCurrentOccludingActivity;
@@ -403,6 +426,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
     private KeyguardFaceAuthInteractor mFaceAuthInteractor;
     private final TaskStackChangeListeners mTaskStackChangeListeners;
     private final IActivityTaskManager mActivityTaskManager;
+    private final DisplayTracker mDisplayTracker;
     private final LockPatternUtils mLockPatternUtils;
     @VisibleForTesting
     @DevicePostureInt
@@ -2187,6 +2211,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
         Trace.beginSection("KeyguardUpdateMonitor#handleStartedWakingUp");
         Assert.isMainThread();
 
+        mAllowedDisplayStateForFaceAuth = true;
         updateFingerprintListeningState(BIOMETRIC_ACTION_UPDATE);
         if (mFaceWakeUpTriggersConfig.shouldTriggerFaceAuthOnWakeUpFrom(pmWakeReason)) {
             FACE_AUTH_UPDATED_STARTED_WAKING_UP.setExtraInfo(pmWakeReason);
@@ -2342,7 +2367,8 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
             Optional<FingerprintInteractiveToAuthProvider> interactiveToAuthProvider,
             FeatureFlags featureFlags,
             TaskStackChangeListeners taskStackChangeListeners,
-            IActivityTaskManager activityTaskManagerService) {
+            IActivityTaskManager activityTaskManagerService,
+            DisplayTracker displayTracker) {
         mContext = context;
         mSubscriptionManager = subscriptionManager;
         mUserTracker = userTracker;
@@ -2390,6 +2416,10 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
                 .collect(Collectors.toSet());
         mTaskStackChangeListeners = taskStackChangeListeners;
         mActivityTaskManager = activityTaskManagerService;
+        mDisplayTracker = displayTracker;
+        if (mFeatureFlags.isEnabled(Flags.STOP_FACE_AUTH_ON_DISPLAY_OFF)) {
+            mDisplayTracker.addDisplayChangeCallback(mDisplayCallback, mainExecutor);
+        }
 
         mHandler = new Handler(mainLooper) {
             @Override
@@ -3199,7 +3229,8 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
                 && (!mSecureCameraLaunched || mAlternateBouncerShowing)
                 && faceAndFpNotAuthenticated
                 && !mGoingToSleep
-                && isPostureAllowedForFaceAuth;
+                && isPostureAllowedForFaceAuth
+                && mAllowedDisplayStateForFaceAuth;
 
         // Aggregate relevant fields for debug logging.
         logListenerModelData(
@@ -3207,6 +3238,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
                     System.currentTimeMillis(),
                     user,
                     shouldListen,
+                    mAllowedDisplayStateForFaceAuth,
                     mAlternateBouncerShowing,
                     mAuthInterruptActive,
                     biometricEnabledForUser,
@@ -4400,6 +4432,7 @@ public class KeyguardUpdateMonitor implements TrustManager.TrustListener, Dumpab
 
         mLockPatternUtils.unregisterStrongAuthTracker(mStrongAuthTracker);
         mTrustManager.unregisterTrustListener(this);
+        mDisplayTracker.removeCallback(mDisplayCallback);
 
         mHandler.removeCallbacksAndMessages(null);
     }

packages/SystemUI/src/com/android/systemui/flags/Flags.kt

@@ -293,6 +293,11 @@ object Flags {
                     "wallpaper_picker_preview_animation"
             )
 
+    /** Stop running face auth when the display state changes to OFF. */
+    // TODO(b/294221702): Tracking bug.
+    @JvmField val STOP_FACE_AUTH_ON_DISPLAY_OFF = resourceBooleanFlag(245,
+            R.bool.flag_stop_face_auth_on_display_off, "stop_face_auth_on_display_off")
+
     // 300 - power menu
     // TODO(b/254512600): Tracking Bug
     @JvmField val POWER_MENU_LITE = releasedFlag(300, "power_menu_lite")

packages/SystemUI/src/com/android/systemui/settings/DisplayTracker.kt

@@ -48,6 +48,9 @@ interface DisplayTracker {
     /** Remove a [Callback] previously added. */
     fun removeCallback(callback: Callback)
 
+    /** Gets the Display with the given displayId */
+    fun getDisplay(displayId: Int): Display
+
     /** Ćallback for notifying of changes. */
     interface Callback {
 

packages/SystemUI/src/com/android/systemui/settings/DisplayTrackerImpl.kt

@@ -115,6 +115,10 @@ internal constructor(
         }
     }
 
+    override fun getDisplay(displayId: Int): Display {
+        return displayManager.getDisplay(displayId)
+    }
+
     @WorkerThread
     private fun onDisplayAdded(displayId: Int, list: List<DisplayTrackerDataItem>) {
         Assert.isNotMainThread()

packages/SystemUI/tests/src/com/android/keyguard/KeyguardUpdateMonitorTest.java

@@ -40,6 +40,7 @@ import static com.android.keyguard.KeyguardUpdateMonitor.DEFAULT_CANCEL_SIGNAL_T
 import static com.android.keyguard.KeyguardUpdateMonitor.HAL_POWER_PRESS_TIMEOUT;
 import static com.android.keyguard.KeyguardUpdateMonitor.getCurrentUser;
 import static com.android.systemui.flags.Flags.FP_LISTEN_OCCLUDING_APPS;
+import static com.android.systemui.flags.Flags.STOP_FACE_AUTH_ON_DISPLAY_OFF;
 import static com.android.systemui.statusbar.policy.DevicePostureController.DEVICE_POSTURE_CLOSED;
 import static com.android.systemui.statusbar.policy.DevicePostureController.DEVICE_POSTURE_OPENED;
 import static com.android.systemui.statusbar.policy.DevicePostureController.DEVICE_POSTURE_UNKNOWN;
@@ -89,6 +90,7 @@ import android.hardware.biometrics.BiometricManager;
 import android.hardware.biometrics.BiometricSourceType;
 import android.hardware.biometrics.ComponentInfoInternal;
 import android.hardware.biometrics.IBiometricEnabledOnKeyguardCallback;
+import android.hardware.display.DisplayManagerGlobal;
 import android.hardware.face.FaceAuthenticateOptions;
 import android.hardware.face.FaceManager;
 import android.hardware.face.FaceSensorProperties;
@@ -121,6 +123,9 @@ import android.test.suitebuilder.annotation.SmallTest;
 import android.testing.AndroidTestingRunner;
 import android.testing.TestableLooper;
 import android.text.TextUtils;
+import android.view.Display;
+import android.view.DisplayAdjustments;
+import android.view.DisplayInfo;
 
 import androidx.annotation.NonNull;
 
@@ -143,6 +148,7 @@ import com.android.systemui.dump.DumpManager;
 import com.android.systemui.flags.FakeFeatureFlags;
 import com.android.systemui.log.SessionTracker;
 import com.android.systemui.plugins.statusbar.StatusBarStateController;
+import com.android.systemui.settings.FakeDisplayTracker;
 import com.android.systemui.settings.UserTracker;
 import com.android.systemui.shared.system.TaskStackChangeListener;
 import com.android.systemui.shared.system.TaskStackChangeListeners;
@@ -304,10 +310,12 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
             mFingerprintAuthenticatorsRegisteredCallback;
     private IFaceAuthenticatorsRegisteredCallback mFaceAuthenticatorsRegisteredCallback;
     private final InstanceId mKeyguardInstanceId = InstanceId.fakeInstanceId(999);
+    private FakeDisplayTracker mDisplayTracker;
 
     @Before
     public void setup() throws RemoteException {
         MockitoAnnotations.initMocks(this);
+        mDisplayTracker = new FakeDisplayTracker(mContext);
         when(mSessionTracker.getSessionId(SESSION_KEYGUARD)).thenReturn(mKeyguardInstanceId);
 
         when(mUserManager.isUserUnlocked(anyInt())).thenReturn(true);
@@ -348,6 +356,7 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
         allowTestableLooperAsMainThread();
         mFeatureFlags = new FakeFeatureFlags();
         mFeatureFlags.set(FP_LISTEN_OCCLUDING_APPS, false);
+        mFeatureFlags.set(STOP_FACE_AUTH_ON_DISPLAY_OFF, false);
 
         when(mSecureSettings.getUriFor(anyString())).thenReturn(mURI);
 
@@ -358,6 +367,11 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
                         anyInt());
 
         mKeyguardUpdateMonitor = new TestableKeyguardUpdateMonitor(mContext);
+        setupBiometrics(mKeyguardUpdateMonitor);
+    }
+
+    private void setupBiometrics(KeyguardUpdateMonitor keyguardUpdateMonitor)
+            throws RemoteException {
         captureAuthenticatorsRegisteredCallbacks();
         setupFaceAuth(/* isClass3 */ false);
         setupFingerprintAuth(/* isClass3 */ true);
@@ -367,9 +381,9 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
         mBiometricEnabledOnKeyguardCallback = mBiometricEnabledCallbackArgCaptor.getValue();
         biometricsEnabledForCurrentUser();
 
-        mHandler = spy(mKeyguardUpdateMonitor.getHandler());
+        mHandler = spy(keyguardUpdateMonitor.getHandler());
         try {
-            FieldSetter.setField(mKeyguardUpdateMonitor,
+            FieldSetter.setField(keyguardUpdateMonitor,
                     KeyguardUpdateMonitor.class.getDeclaredField("mHandler"), mHandler);
         } catch (NoSuchFieldException e) {
 
@@ -3029,6 +3043,79 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
         verify(callback).onBiometricEnrollmentStateChanged(BiometricSourceType.FACE);
     }
 
+    @Test
+    public void stopFaceAuthOnDisplayOffFlagNotEnabled_doNotRegisterForDisplayCallback() {
+        assertThat(mDisplayTracker.getDisplayCallbacks().size()).isEqualTo(0);
+    }
+
+    @Test
+    public void onDisplayOn_nothingHappens() throws RemoteException {
+        // GIVEN
+        keyguardIsVisible();
+        enableStopFaceAuthOnDisplayOff();
+
+        // WHEN the default display state changes to ON
+        triggerDefaultDisplayStateChangeToOn();
+
+        // THEN face auth is NOT started since we rely on STARTED_WAKING_UP to start face auth,
+        // NOT the display on event
+        verifyFaceAuthenticateNeverCalled();
+        verifyFaceDetectNeverCalled();
+    }
+
+    @Test
+    public void onDisplayOff_stopFaceAuth() throws RemoteException {
+        enableStopFaceAuthOnDisplayOff();
+
+        // GIVEN device is listening for face
+        mKeyguardUpdateMonitor.setKeyguardShowing(true, false);
+        mKeyguardUpdateMonitor.dispatchStartedWakingUp(PowerManager.WAKE_REASON_POWER_BUTTON);
+        mTestableLooper.processAllMessages();
+        verifyFaceAuthenticateCall();
+
+        final CancellationSignal faceCancel = spy(mKeyguardUpdateMonitor.mFaceCancelSignal);
+        mKeyguardUpdateMonitor.mFaceCancelSignal = faceCancel;
+        KeyguardUpdateMonitorCallback callback = mock(KeyguardUpdateMonitorCallback.class);
+        mKeyguardUpdateMonitor.registerCallback(callback);
+
+        // WHEN the default display state changes to OFF
+        triggerDefaultDisplayStateChangeToOff();
+
+        // THEN face listening is stopped.
+        verify(faceCancel).cancel();
+        verify(callback).onBiometricRunningStateChanged(
+                eq(false), eq(BiometricSourceType.FACE)); // beverlyt
+
+    }
+
+    private void triggerDefaultDisplayStateChangeToOn() {
+        triggerDefaultDisplayStateChangeTo(true);
+    }
+
+    private void triggerDefaultDisplayStateChangeToOff() {
+        triggerDefaultDisplayStateChangeTo(false);
+    }
+
+    /**
+     * @param on true for Display.STATE_ON, else Display.STATE_OFF
+     */
+    private void triggerDefaultDisplayStateChangeTo(boolean on) {
+        DisplayManagerGlobal displayManagerGlobal = mock(DisplayManagerGlobal.class);
+        DisplayInfo displayInfoWithDisplayState = new DisplayInfo();
+        displayInfoWithDisplayState.state = on ? Display.STATE_ON : Display.STATE_OFF;
+        when(displayManagerGlobal.getDisplayInfo(mDisplayTracker.getDefaultDisplayId()))
+                .thenReturn(displayInfoWithDisplayState);
+        mDisplayTracker.setAllDisplays(new Display[]{
+                new Display(
+                        displayManagerGlobal,
+                        mDisplayTracker.getDefaultDisplayId(),
+                        displayInfoWithDisplayState,
+                        DisplayAdjustments.DEFAULT_DISPLAY_ADJUSTMENTS
+                )
+        });
+        mDisplayTracker.triggerOnDisplayChanged(mDisplayTracker.getDefaultDisplayId());
+    }
+
     private void verifyFingerprintAuthenticateNeverCalled() {
         verify(mFingerprintManager, never()).authenticate(any(), any(), any(), any(), any());
         verify(mFingerprintManager, never()).authenticate(any(), any(), any(), any(), anyInt(),
@@ -3297,6 +3384,18 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
         mTestableLooper.processAllMessages();
     }
 
+    private void enableStopFaceAuthOnDisplayOff() throws RemoteException {
+        cleanupKeyguardUpdateMonitor();
+        clearInvocations(mFaceManager);
+        clearInvocations(mFingerprintManager);
+        clearInvocations(mBiometricManager);
+        clearInvocations(mStatusBarStateController);
+        mFeatureFlags.set(STOP_FACE_AUTH_ON_DISPLAY_OFF, true);
+        mKeyguardUpdateMonitor = new TestableKeyguardUpdateMonitor(mContext);
+        setupBiometrics(mKeyguardUpdateMonitor);
+        assertThat(mDisplayTracker.getDisplayCallbacks().size()).isEqualTo(1);
+    }
+
     private Intent putPhoneInfo(Intent intent, Bundle data, Boolean simInited) {
         int subscription = simInited
                 ? 1/* mock subid=1 */ : SubscriptionManager.PLACEHOLDER_SUBSCRIPTION_ID_BASE;
@@ -3374,7 +3473,7 @@ public class KeyguardUpdateMonitorTest extends SysuiTestCase {
                     mPackageManager, mFaceManager, mFingerprintManager, mBiometricManager,
                     mFaceWakeUpTriggersConfig, mDevicePostureController,
                     Optional.of(mInteractiveToAuthProvider), mFeatureFlags,
-                    mTaskStackChangeListeners, mActivityTaskManager);
+                    mTaskStackChangeListeners, mActivityTaskManager, mDisplayTracker);
             setStrongAuthTracker(KeyguardUpdateMonitorTest.this.mStrongAuthTracker);
         }
 

packages/SystemUI/tests/utils/src/com/android/systemui/settings/FakeDisplayTracker.kt

@@ -26,7 +26,7 @@ class FakeDisplayTracker constructor(val context: Context) : DisplayTracker {
     override var defaultDisplayId: Int = Display.DEFAULT_DISPLAY
     override var allDisplays: Array<Display> = displayManager.displays
 
-    private val displayCallbacks: MutableList<DisplayTracker.Callback> = ArrayList()
+    val displayCallbacks: MutableList<DisplayTracker.Callback> = ArrayList()
     private val brightnessCallbacks: MutableList<DisplayTracker.Callback> = ArrayList()
     override fun addDisplayChangeCallback(callback: DisplayTracker.Callback, executor: Executor) {
         displayCallbacks.add(callback)
@@ -43,12 +43,12 @@ class FakeDisplayTracker constructor(val context: Context) : DisplayTracker {
         brightnessCallbacks.remove(callback)
     }
 
-    fun setDefaultDisplay(displayId: Int) {
+    override fun getDisplay(displayId: Int): Display {
-        defaultDisplayId = displayId
+        return allDisplays.filter { display -> display.displayId == displayId }[0]
     }
 
-    fun setDisplays(displays: Array<Display>) {
+    fun setDefaultDisplay(displayId: Int) {
-        allDisplays = displays
+        defaultDisplayId = displayId
     }
 
     fun triggerOnDisplayAdded(displayId: Int) {