WM: Prevent secondary display focus while keyguard is up

Fixes an issue where input intended for the keyguard could end up going
to a different display.

To prevent this, make sure that only the default display can get focused
when the keyguard is showing.

Change-Id: I6463c44aedca06930d2c9bda7c45ffd93141308c
Fixes: 71786287
Test: atest DisplayContentTests

services/core/java/com/android/server/policy/PhoneWindowManager.java

@@ -234,7 +234,6 @@ import android.util.SparseArray;
 import android.util.proto.ProtoOutputStream;
 import android.view.Display;
 import android.view.DisplayCutout;
-import android.view.DisplayInfo;
 import android.view.Gravity;
 import android.view.HapticFeedbackConstants;
 import android.view.IApplicationToken;
@@ -2287,6 +2286,11 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     public void onTrustedChanged() {
                         mWindowManagerFuncs.notifyKeyguardTrustedChanged();
                     }
+
+                    @Override
+                    public void onShowingChanged() {
+                        mWindowManagerFuncs.onKeyguardShowingAndNotOccludedChanged();
+                    }
                 });
         mScreenshotHelper = new ScreenshotHelper(mContext);
     }

services/core/java/com/android/server/policy/WindowManagerPolicy.java

@@ -660,6 +660,11 @@ public interface WindowManagerPolicy extends WindowManagerPolicyConstants {
          * abort animations that have no timeout, in case they got stuck.
          */
         void triggerAnimationFailsafe();
+
+        /**
+         * The keyguard showing state has changed
+         */
+        void onKeyguardShowingAndNotOccludedChanged();
     }
 
     /** Window has been added to the screen. */

services/core/java/com/android/server/policy/keyguard/KeyguardStateMonitor.java

@@ -94,6 +94,7 @@ public class KeyguardStateMonitor extends IKeyguardStateCallback.Stub {
     public void onShowingStateChanged(boolean showing) {
         mIsShowing = showing;
 
+        mCallback.onShowingChanged();
         try {
             mKeystoreService.onKeyguardVisibilityChanged(showing, mCurrentUserId);
         } catch (RemoteException e) {
@@ -132,6 +133,7 @@ public class KeyguardStateMonitor extends IKeyguardStateCallback.Stub {
 
     public interface StateCallback {
         void onTrustedChanged();
+        void onShowingChanged();
     }
 
     public void dump(String prefix, PrintWriter pw) {

services/core/java/com/android/server/wm/RootWindowContainer.java

@@ -157,10 +157,18 @@ class RootWindowContainer extends WindowContainer<DisplayContent> {
     }
 
     WindowState computeFocusedWindow() {
+        // While the keyguard is showing, we must focus anything besides the main display.
+        // Otherwise we risk input not going to the keyguard when the user expects it to.
+        final boolean forceDefaultDisplay = mService.isKeyguardShowingAndNotOccluded();
+
         for (int i = mChildren.size() - 1; i >= 0; i--) {
             final DisplayContent dc = mChildren.get(i);
             final WindowState win = dc.findFocusedWindow();
             if (win != null) {
+                if (forceDefaultDisplay && !dc.isDefaultDisplay) {
+                    EventLog.writeEvent(0x534e4554, "71786287", win.mOwnerUid, "");
+                    continue;
+                }
                 return win;
             }
         }

services/core/java/com/android/server/wm/WindowManagerService.java

@@ -2837,6 +2837,11 @@ public class WindowManagerService extends IWindowManager.Stub
         mH.sendEmptyMessage(H.ANIMATION_FAILSAFE);
     }
 
+    @Override
+    public void onKeyguardShowingAndNotOccludedChanged() {
+        mH.sendEmptyMessage(H.RECOMPUTE_FOCUS);
+    }
+
     /**
      * Starts deferring layout passes. Useful when doing multiple changes but to optimize
      * performance, only one layout pass should be done. This can be called multiple times, and
@@ -4611,6 +4616,7 @@ public class WindowManagerService extends IWindowManager.Stub
         public static final int SET_HAS_OVERLAY_UI = 58;
         public static final int SET_RUNNING_REMOTE_ANIMATION = 59;
         public static final int ANIMATION_FAILSAFE = 60;
+        public static final int RECOMPUTE_FOCUS = 61;
 
         /**
          * Used to denote that an integer field in a message will not be used.
@@ -5037,6 +5043,13 @@ public class WindowManagerService extends IWindowManager.Stub
                     }
                 }
                 break;
+                case RECOMPUTE_FOCUS: {
+                    synchronized (mWindowMap) {
+                        updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL,
+                                true /* updateInputWindows */);
+                    }
+                }
+                break;
             }
             if (DEBUG_WINDOW_TRACE) {
                 Slog.v(TAG_WM, "handleMessage: exit");

services/tests/servicestests/src/com/android/server/wm/DisplayContentTests.java

@@ -329,6 +329,21 @@ public class DisplayContentTests extends WindowTestsBase {
         assertEquals(window1, sWm.mRoot.computeFocusedWindow());
     }
 
+    @Test
+    public void testKeyguard_preventsSecondaryDisplayFocus() throws Exception {
+        final WindowState keyguard = createWindow(null, TYPE_STATUS_BAR,
+                sWm.getDefaultDisplayContentLocked(), "keyguard");
+        assertEquals(keyguard, sWm.mRoot.computeFocusedWindow());
+
+        // Add a window to a second display, and it should be focused
+        final DisplayContent dc = createNewDisplay();
+        final WindowState win = createWindow(null, TYPE_BASE_APPLICATION, dc, "win");
+        assertEquals(win, sWm.mRoot.computeFocusedWindow());
+
+        mWmRule.getWindowManagerPolicy().keyguardShowingAndNotOccluded = true;
+        assertEquals(keyguard, sWm.mRoot.computeFocusedWindow());
+    }
+
     /**
      * This tests setting the maximum ui width on a display.
      */

services/tests/servicestests/src/com/android/server/wm/TestWindowManagerPolicy.java

@@ -51,6 +51,7 @@ class TestWindowManagerPolicy implements WindowManagerPolicy {
     private final Supplier<WindowManagerService> mWmSupplier;
 
     int rotationToReport = 0;
+    boolean keyguardShowingAndNotOccluded = false;
 
     private Runnable mRunnableWhenAddingSplashScreen;
 
@@ -338,7 +339,7 @@ class TestWindowManagerPolicy implements WindowManagerPolicy {
 
     @Override
     public boolean isKeyguardLocked() {
-        return false;
+        return keyguardShowingAndNotOccluded;
     }
 
     @Override
@@ -358,7 +359,7 @@ class TestWindowManagerPolicy implements WindowManagerPolicy {
 
     @Override
     public boolean isKeyguardShowingAndNotOccluded() {
-        return false;
+        return keyguardShowingAndNotOccluded;
     }
 
     @Override

services/tests/servicestests/src/com/android/server/wm/WindowManagerServiceRule.java

@@ -59,6 +59,7 @@ import org.mockito.invocation.InvocationOnMock;
 public class WindowManagerServiceRule implements TestRule {
 
     private WindowManagerService mService;
+    private TestWindowManagerPolicy mPolicy;
 
     @Override
     public Statement apply(Statement base, Description description) {
@@ -108,7 +109,7 @@ public class WindowManagerServiceRule implements TestRule {
                 }
 
                 mService = WindowManagerService.main(context, ims, true, false,
-                        false, new TestWindowManagerPolicy(
+                        false, mPolicy = new TestWindowManagerPolicy(
                                 WindowManagerServiceRule.this::getWindowManagerService));
 
                 mService.onInitReady();
@@ -132,6 +133,7 @@ public class WindowManagerServiceRule implements TestRule {
                 waitUntilWindowManagerHandlersIdle();
                 removeServices();
                 mService = null;
+                mPolicy = null;
             }
         };
     }
@@ -140,6 +142,10 @@ public class WindowManagerServiceRule implements TestRule {
         return mService;
     }
 
+    public TestWindowManagerPolicy getWindowManagerPolicy() {
+        return mPolicy;
+    }
+
     public void waitUntilWindowManagerHandlersIdle() {
         final WindowManagerService wm = getWindowManagerService();
         if (wm != null) {