diff --git a/services/core/java/com/android/server/policy/PhoneWindowManager.java b/services/core/java/com/android/server/policy/PhoneWindowManager.java
index 14c0879..c79b21c 100644
--- a/services/core/java/com/android/server/policy/PhoneWindowManager.java
+++ b/services/core/java/com/android/server/policy/PhoneWindowManager.java
@@ -25,13 +25,82 @@
 import static android.content.res.Configuration.EMPTY;
 import static android.content.res.Configuration.UI_MODE_TYPE_CAR;
 import static android.content.res.Configuration.UI_MODE_TYPE_MASK;
-import static android.view.WindowManager.DOCKED_TOP;
 import static android.view.WindowManager.DOCKED_LEFT;
 import static android.view.WindowManager.DOCKED_RIGHT;
+import static android.view.WindowManager.DOCKED_TOP;
 import static android.view.WindowManager.INPUT_CONSUMER_NAVIGATION;
+import static android.view.WindowManager.LayoutParams.FIRST_APPLICATION_WINDOW;
+import static android.view.WindowManager.LayoutParams.FIRST_SUB_WINDOW;
+import static android.view.WindowManager.LayoutParams.FIRST_SYSTEM_WINDOW;
+import static android.view.WindowManager.LayoutParams.FLAG_ALLOW_LOCK_WHILE_SCREEN_ON;
+import static android.view.WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS;
+import static android.view.WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN;
+import static android.view.WindowManager.LayoutParams.FLAG_FULLSCREEN;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_ATTACHED_IN_DECOR;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_IN_OVERSCAN;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
+import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
+import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED;
+import static android.view.WindowManager.LayoutParams.LAST_APPLICATION_WINDOW;
+import static android.view.WindowManager.LayoutParams.LAST_SUB_WINDOW;
+import static android.view.WindowManager.LayoutParams.LAST_SYSTEM_WINDOW;
+import static android.view.WindowManager.LayoutParams.MATCH_PARENT;
+import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_FORCE_DRAW_STATUS_BAR_BACKGROUND;
+import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_FORCE_STATUS_BAR_VISIBLE_TRANSPARENT;
+import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_KEYGUARD;
+import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_SHOW_FOR_ALL_USERS;
+import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_SYSTEM_ERROR;
+import static android.view.WindowManager.LayoutParams.ROTATION_ANIMATION_CROSSFADE;
+import static android.view.WindowManager.LayoutParams.ROTATION_ANIMATION_JUMPCUT;
+import static android.view.WindowManager.LayoutParams.ROTATION_ANIMATION_ROTATE;
+import static android.view.WindowManager.LayoutParams.ROTATION_ANIMATION_SEAMLESS;
+import static android.view.WindowManager.LayoutParams.SOFT_INPUT_ADJUST_NOTHING;
+import static android.view.WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE;
+import static android.view.WindowManager.LayoutParams.SOFT_INPUT_MASK_ADJUST;
+import static android.view.WindowManager.LayoutParams.TYPE_ACCESSIBILITY_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ABOVE_SUB_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_STARTING;
+import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_SUB_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_BOOT_PROGRESS;
+import static android.view.WindowManager.LayoutParams.TYPE_DISPLAY_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_DOCK_DIVIDER;
+import static android.view.WindowManager.LayoutParams.TYPE_DRAG;
+import static android.view.WindowManager.LayoutParams.TYPE_DREAM;
+import static android.view.WindowManager.LayoutParams.TYPE_INPUT_CONSUMER;
+import static android.view.WindowManager.LayoutParams.TYPE_INPUT_METHOD;
+import static android.view.WindowManager.LayoutParams.TYPE_INPUT_METHOD_DIALOG;
+import static android.view.WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG;
+import static android.view.WindowManager.LayoutParams.TYPE_MAGNIFICATION_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR;
+import static android.view.WindowManager.LayoutParams.TYPE_NAVIGATION_BAR_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_PHONE;
+import static android.view.WindowManager.LayoutParams.TYPE_POINTER;
+import static android.view.WindowManager.LayoutParams.TYPE_PRIORITY_PHONE;
+import static android.view.WindowManager.LayoutParams.TYPE_PRIVATE_PRESENTATION;
+import static android.view.WindowManager.LayoutParams.TYPE_QS_DIALOG;
+import static android.view.WindowManager.LayoutParams.TYPE_SCREENSHOT;
+import static android.view.WindowManager.LayoutParams.TYPE_SEARCH_BAR;
+import static android.view.WindowManager.LayoutParams.TYPE_SECURE_SYSTEM_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR;
+import static android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_STATUS_BAR_SUB_PANEL;
+import static android.view.WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;
+import static android.view.WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG;
+import static android.view.WindowManager.LayoutParams.TYPE_SYSTEM_ERROR;
+import static android.view.WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_TOAST;
+import static android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION;
+import static android.view.WindowManager.LayoutParams.TYPE_VOICE_INTERACTION_STARTING;
+import static android.view.WindowManager.LayoutParams.TYPE_VOLUME_OVERLAY;
+import static android.view.WindowManager.LayoutParams.TYPE_WALLPAPER;
 import static android.view.WindowManager.TAKE_SCREENSHOT_FULLSCREEN;
 import static android.view.WindowManager.TAKE_SCREENSHOT_SELECTED_REGION;
-import static android.view.WindowManager.LayoutParams.*;
 import static android.view.WindowManagerPolicy.WindowManagerFuncs.CAMERA_LENS_COVERED;
 import static android.view.WindowManagerPolicy.WindowManagerFuncs.CAMERA_LENS_COVER_ABSENT;
 import static android.view.WindowManagerPolicy.WindowManagerFuncs.CAMERA_LENS_UNCOVERED;
@@ -113,10 +182,10 @@
 import android.util.DisplayMetrics;
 import android.util.EventLog;
 import android.util.Log;
+import android.util.LongSparseArray;
 import android.util.MutableBoolean;
 import android.util.Slog;
 import android.util.SparseArray;
-import android.util.LongSparseArray;
 import android.view.Display;
 import android.view.Gravity;
 import android.view.HapticFeedbackConstants;
@@ -144,10 +213,11 @@
 import android.view.animation.Animation;
 import android.view.animation.AnimationSet;
 import android.view.animation.AnimationUtils;
+
 import com.android.internal.R;
 import com.android.internal.logging.MetricsLogger;
-import com.android.internal.policy.PhoneWindow;
 import com.android.internal.policy.IShortcutService;
+import com.android.internal.policy.PhoneWindow;
 import com.android.internal.statusbar.IStatusBarService;
 import com.android.internal.util.ScreenShapeHelper;
 import com.android.internal.widget.PointerLocationView;
@@ -282,8 +352,6 @@
     /**
      * Keyguard stuff
      */
-    private WindowState mKeyguardScrim;
-    private boolean mKeyguardHidden;
     private boolean mKeyguardDrawnOnce;
 
     /* Table of Application Launch keys.  Maps from key codes to intent categories.
@@ -2303,7 +2371,6 @@
             case TYPE_BOOT_PROGRESS:
             case TYPE_DISPLAY_OVERLAY:
             case TYPE_INPUT_CONSUMER:
-            case TYPE_KEYGUARD_SCRIM:
             case TYPE_KEYGUARD_DIALOG:
             case TYPE_MAGNIFICATION_OVERLAY:
             case TYPE_NAVIGATION_BAR:
@@ -2520,9 +2587,6 @@
         case TYPE_INPUT_METHOD_DIALOG:
             // on-screen keyboards and other such input method user interfaces go here.
             return 13;
-        case TYPE_KEYGUARD_SCRIM:
-            // the safety window that shows behind keyguard while keyguard is starting
-            return 14;
         case TYPE_STATUS_BAR_SUB_PANEL:
             return 15;
         case TYPE_STATUS_BAR:
@@ -2671,7 +2735,6 @@
             case TYPE_NAVIGATION_BAR:
             case TYPE_WALLPAPER:
             case TYPE_DREAM:
-            case TYPE_KEYGUARD_SCRIM:
                 return false;
             default:
                 // Hide only windows below the keyguard host window.
@@ -2908,12 +2971,6 @@
                         android.Manifest.permission.STATUS_BAR_SERVICE,
                         "PhoneWindowManager");
                 break;
-            case TYPE_KEYGUARD_SCRIM:
-                if (mKeyguardScrim != null) {
-                    return WindowManagerGlobal.ADD_MULTIPLE_SINGLETON;
-                }
-                mKeyguardScrim = win;
-                break;
         }
         return WindowManagerGlobal.ADD_OKAY;
     }
@@ -2924,11 +2981,7 @@
         if (mStatusBar == win) {
             mStatusBar = null;
             mStatusBarController.setWindow(null);
-            mKeyguardDelegate.showScrim();
-        } else if (mKeyguardScrim == win) {
-            Log.v(TAG, "Removing keyguard scrim");
-            mKeyguardScrim = null;
-        } if (mNavigationBar == win) {
+        } else if (mNavigationBar == win) {
             mNavigationBar = null;
             mNavigationBarController.setWindow(null);
         }
@@ -3240,8 +3293,7 @@
             WindowManager.LayoutParams attrs = win != null ? win.getAttrs() : null;
             if (attrs != null) {
                 final int type = attrs.type;
-                if (type == WindowManager.LayoutParams.TYPE_KEYGUARD_SCRIM
-                        || type == WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG
+                if (type == TYPE_KEYGUARD_DIALOG
                         || (attrs.privateFlags & PRIVATE_FLAG_KEYGUARD) != 0) {
                     // the "app" is keyguard, so give it the key
                     return 0;
diff --git a/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java b/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java
index 2069f24..74b882e 100644
--- a/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java
+++ b/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java
@@ -1,12 +1,13 @@
 package com.android.server.policy.keyguard;
 
+import android.app.ActivityManager;
+import android.app.ActivityManagerInternal;
+import android.app.ActivityManagerNative;
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.ServiceConnection;
-import android.content.pm.ActivityInfo;
 import android.content.res.Resources;
-import android.graphics.PixelFormat;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
@@ -15,13 +16,12 @@
 import android.util.Log;
 import android.util.Slog;
 import android.view.View;
-import android.view.ViewGroup;
-import android.view.WindowManager;
 import android.view.WindowManagerPolicy.OnKeyguardExitResult;
 
 import com.android.internal.policy.IKeyguardDrawnCallback;
 import com.android.internal.policy.IKeyguardExitCallback;
 import com.android.internal.policy.IKeyguardService;
+import com.android.server.LocalServices;
 import com.android.server.UiThread;
 
 import java.io.PrintWriter;
@@ -45,22 +45,13 @@
 
     protected KeyguardServiceWrapper mKeyguardService;
     private final Context mContext;
-    private final View mScrim; // shown if keyguard crashes
-    private final Handler mScrimHandler;
+    private final Handler mHandler;
     private final KeyguardState mKeyguardState = new KeyguardState();
     private DrawnListener mDrawnListenerWhenConnect;
 
     private static final class KeyguardState {
         KeyguardState() {
-            // Assume keyguard is showing and secure until we know for sure. This is here in
-            // the event something checks before the service is actually started.
-            // KeyguardService itself should default to this state until the real state is known.
-            showing = true;
-            showingAndNotOccluded = true;
-            secure = true;
-            deviceHasKeyguard = true;
-            enabled = true;
-            currentUser = UserHandle.USER_NULL;
+            reset();
         }
         boolean showing;
         boolean showingAndNotOccluded;
@@ -76,6 +67,18 @@
         public boolean bootCompleted;
         public int screenState;
         public int interactiveState;
+
+        private void reset() {
+            // Assume keyguard is showing and secure until we know for sure. This is here in
+            // the event something checks before the service is actually started.
+            // KeyguardService itself should default to this state until the real state is known.
+            showing = true;
+            showingAndNotOccluded = true;
+            secure = true;
+            deviceHasKeyguard = true;
+            enabled = true;
+            currentUser = UserHandle.USER_NULL;
+        }
     };
 
     public interface DrawnListener {
@@ -96,7 +99,6 @@
             if (mDrawnListener != null) {
                 mDrawnListener.onDrawn();
             }
-            hideScrim();
         }
     };
 
@@ -119,8 +121,7 @@
 
     public KeyguardServiceDelegate(Context context) {
         mContext = context;
-        mScrimHandler = UiThread.getHandler();
-        mScrim = createScrim(context, mScrimHandler);
+        mHandler = UiThread.getHandler();
     }
 
     public void bindService(Context context) {
@@ -133,7 +134,7 @@
         intent.setComponent(keyguardComponent);
 
         if (!context.bindServiceAsUser(intent, mKeyguardConnection,
-                Context.BIND_AUTO_CREATE, mScrimHandler, UserHandle.SYSTEM)) {
+                Context.BIND_AUTO_CREATE, mHandler, UserHandle.SYSTEM)) {
             Log.v(TAG, "*** Keyguard: can't bind to " + keyguardComponent);
             mKeyguardState.showing = false;
             mKeyguardState.showingAndNotOccluded = false;
@@ -143,7 +144,6 @@
                 // is at least self-healing but a race condition here can lead to the scrim being
                 // stuck on keyguard-less devices.
                 mKeyguardState.deviceHasKeyguard = false;
-                hideScrim();
             }
         } else {
             if (DEBUG) Log.v(TAG, "*** Keyguard started");
@@ -192,8 +192,15 @@
         public void onServiceDisconnected(ComponentName name) {
             if (DEBUG) Log.v(TAG, "*** Keyguard disconnected (boo!)");
             mKeyguardService = null;
+            mKeyguardState.reset();
+            mHandler.post(() -> {
+                try {
+                    ActivityManagerNative.getDefault().setLockScreenShown(true);
+                } catch (RemoteException e) {
+                    // Local call.
+                }
+            });
         }
-
     };
 
     public boolean isShowing() {
@@ -297,7 +304,6 @@
             // This shouldn't happen, but if it does, show the scrim immediately and
             // invoke the listener's callback after the service actually connects.
             mDrawnListenerWhenConnect = drawnListener;
-            showScrim();
         }
         mKeyguardState.screenState = SCREEN_STATE_TURNING_ON;
     }
@@ -365,61 +371,6 @@
         }
     }
 
-    private static View createScrim(Context context, Handler handler) {
-        final View view = new View(context);
-
-        int flags = WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN
-                | WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR
-                | WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN
-                | WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER
-                ;
-
-        final int stretch = ViewGroup.LayoutParams.MATCH_PARENT;
-        final int type = WindowManager.LayoutParams.TYPE_KEYGUARD_SCRIM;
-        final WindowManager.LayoutParams lp = new WindowManager.LayoutParams(
-                stretch, stretch, type, flags, PixelFormat.TRANSLUCENT);
-        lp.softInputMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE;
-        lp.screenOrientation = ActivityInfo.SCREEN_ORIENTATION_NOSENSOR;
-        lp.privateFlags |= WindowManager.LayoutParams.PRIVATE_FLAG_FAKE_HARDWARE_ACCELERATED;
-        lp.setTitle("KeyguardScrim");
-        final WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
-        // Disable pretty much everything in statusbar until keyguard comes back and we know
-        // the state of the world.
-        view.setSystemUiVisibility(View.STATUS_BAR_DISABLE_HOME
-                | View.STATUS_BAR_DISABLE_BACK
-                | View.STATUS_BAR_DISABLE_RECENT
-                | View.STATUS_BAR_DISABLE_EXPAND
-                | View.STATUS_BAR_DISABLE_SEARCH);
-        handler.post(new Runnable() {
-            @Override
-            public void run() {
-                wm.addView(view, lp);
-            }
-        });
-        return view;
-    }
-
-    public void showScrim() {
-        synchronized (mKeyguardState) {
-            if (!mKeyguardState.deviceHasKeyguard) return;
-            mScrimHandler.post(new Runnable() {
-                @Override
-                public void run() {
-                    mScrim.setVisibility(View.VISIBLE);
-                }
-            });
-        }
-    }
-
-    public void hideScrim() {
-        mScrimHandler.post(new Runnable() {
-            @Override
-            public void run() {
-                mScrim.setVisibility(View.GONE);
-            }
-        });
-    }
-
     public void onBootCompleted() {
         if (mKeyguardService != null) {
             mKeyguardService.onBootCompleted();
@@ -427,12 +378,6 @@
         mKeyguardState.bootCompleted = true;
     }
 
-    public void onActivityDrawn() {
-        if (mKeyguardService != null) {
-            mKeyguardService.onActivityDrawn();
-        }
-    }
-
     public void dump(String prefix, PrintWriter pw) {
         pw.println(prefix + TAG);
         prefix += "  ";
diff --git a/services/core/java/com/android/server/wm/AccessibilityController.java b/services/core/java/com/android/server/wm/AccessibilityController.java
index bde65ed..670b9cc 100644
--- a/services/core/java/com/android/server/wm/AccessibilityController.java
+++ b/services/core/java/com/android/server/wm/AccessibilityController.java
@@ -1283,8 +1283,7 @@
         }
 
         private static boolean isReportedWindowType(int windowType) {
-            return (windowType != WindowManager.LayoutParams.TYPE_KEYGUARD_SCRIM
-                    && windowType != WindowManager.LayoutParams.TYPE_WALLPAPER
+            return (windowType != WindowManager.LayoutParams.TYPE_WALLPAPER
                     && windowType != WindowManager.LayoutParams.TYPE_BOOT_PROGRESS
                     && windowType != WindowManager.LayoutParams.TYPE_DISPLAY_OVERLAY
                     && windowType != WindowManager.LayoutParams.TYPE_DRAG
diff --git a/services/core/java/com/android/server/wm/WindowToken.java b/services/core/java/com/android/server/wm/WindowToken.java
index c9bdb9f..cf1a98a 100644
--- a/services/core/java/com/android/server/wm/WindowToken.java
+++ b/services/core/java/com/android/server/wm/WindowToken.java
@@ -20,7 +20,6 @@
 import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
 import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_KEYGUARD;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_STARTING;
-import static android.view.WindowManager.LayoutParams.TYPE_KEYGUARD_SCRIM;
 
 import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_ADD_REMOVE;
 import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_FOCUS;
@@ -402,9 +401,8 @@
             // is currently on screen, i.e. not hidden by policy.
             int insertionIndex = 0;
             if (visible && wallpaperTarget != null) {
-                final int type = wallpaperTarget.mAttrs.type;
                 final int privateFlags = wallpaperTarget.mAttrs.privateFlags;
-                if (((privateFlags & PRIVATE_FLAG_KEYGUARD) != 0 || type == TYPE_KEYGUARD_SCRIM)) {
+                if ((privateFlags & PRIVATE_FLAG_KEYGUARD) != 0) {
                     insertionIndex = Math.min(windowList.indexOf(wallpaperTarget),
                             findLowestWindowOnScreen(windowList));
                 }