Gestures: Assemble per-window exclusion zones

Adds a facility to listen for per-window exclusion zones and
assembles them into a per-display exclusion zone ready for
consumption by interested parties.

Bug: 126360272
Test: atest DisplayContentTests
Change-Id: Ic186f86ca551af98a5f77beb254d257c281a4160

13 files changed, 397 insertions, 4 deletions

diff --git a/Android.bp b/Android.bp
index e8f35611e74b..fe9757fdf496 100644
--- a/Android.bp
+++ b/Android.bp
@@ -383,6 +383,7 @@ java_defaults {
         "core/java/android/view/IRecentsAnimationRunner.aidl",
         "core/java/android/view/IRemoteAnimationFinishedCallback.aidl",
         "core/java/android/view/IRotationWatcher.aidl",
+        "core/java/android/view/ISystemGestureExclusionListener.aidl",
         "core/java/android/view/IWallpaperVisibilityListener.aidl",
         "core/java/android/view/IWindow.aidl",
         "core/java/android/view/IWindowFocusObserver.aidl",
diff --git a/core/java/android/view/ISystemGestureExclusionListener.aidl b/core/java/android/view/ISystemGestureExclusionListener.aidl
new file mode 100644
index 000000000000..a032625547d2
--- /dev/null
+++ b/core/java/android/view/ISystemGestureExclusionListener.aidl
@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2019, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view;
+
+import android.graphics.Region;
+
+/**
+ * Listener for changes to the system gesture exclusion region
+ *
+ * {@hide}
+ */
+oneway interface ISystemGestureExclusionListener {
+    /**
+     * Called when the system gesture exclusion for the given display changed.
+     * @param displayId the display whose system gesture exclusion changed
+     * @param systemGestureExclusion a {@code Region} where the app would like priority over the
+     *                               system gestures, in display coordinates.
+     */
+    void onSystemGestureExclusionChanged(int displayId, in Region systemGestureExclusion);
+}
\ No newline at end of file
diff --git a/core/java/android/view/IWindowManager.aidl b/core/java/android/view/IWindowManager.aidl
index e32c4e136a6e..42f7d9e50555 100644
--- a/core/java/android/view/IWindowManager.aidl
+++ b/core/java/android/view/IWindowManager.aidl
@@ -40,6 +40,7 @@ import android.view.IOnKeyguardExitResult;
 import android.view.IPinnedStackListener;
 import android.view.RemoteAnimationAdapter;
 import android.view.IRotationWatcher;
+import android.view.ISystemGestureExclusionListener;
 import android.view.IWallpaperVisibilityListener;
 import android.view.IWindowSession;
 import android.view.IWindowSessionCallback;
@@ -281,6 +282,18 @@ interface IWindowManager
         int displayId);
 
     /**
+     * Registers a system gesture exclusion listener for a given display.
+     */
+    void registerSystemGestureExclusionListener(ISystemGestureExclusionListener listener,
+        int displayId);
+
+    /**
+     * Unregisters a system gesture exclusion listener for a given display.
+     */
+    void unregisterSystemGestureExclusionListener(ISystemGestureExclusionListener listener,
+        int displayId);
+
+    /**
      * Used only for assist -- request a screenshot of the current application.
      */
     boolean requestAssistScreenshot(IAssistDataReceiver receiver);
diff --git a/core/java/android/view/IWindowSession.aidl b/core/java/android/view/IWindowSession.aidl
index 1fcd4321cdde..87efb3fbf6c0 100644
--- a/core/java/android/view/IWindowSession.aidl
+++ b/core/java/android/view/IWindowSession.aidl
@@ -32,6 +32,8 @@ import android.view.InsetsState;
 import android.view.Surface;
 import android.view.SurfaceControl;
 
+import java.util.List;
+
 /**
  * System private per-application interface to the window manager.
  *
@@ -265,4 +267,10 @@ interface IWindowSession {
      * that new state.
      */
     void insetsModified(IWindow window, in InsetsState state);
+
+
+    /**
+     * Called when the system gesture exclusion has changed.
+     */
+    void reportSystemGestureExclusionChanged(IWindow window, in List<Rect> exclusionRects);
 }
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 9222bd62f1c4..14df87c39ae1 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -3990,7 +3990,11 @@ public final class ViewRootImpl implements ViewParent,
     void systemGestureExclusionChanged() {
         final List<Rect> rectsForWindowManager = mGestureExclusionTracker.computeChangedRects();
         if (rectsForWindowManager != null) {
-            // TODO Send to WM
+            try {
+                mWindowSession.reportSystemGestureExclusionChanged(mWindow, rectsForWindowManager);
+            } catch (RemoteException e) {
+                throw e.rethrowFromSystemServer();
+            }
             mAttachInfo.mTreeObserver
                     .dispatchOnSystemGestureExclusionRectsChanged(rectsForWindowManager);
         }
diff --git a/core/java/com/android/internal/widget/PointerLocationView.java b/core/java/com/android/internal/widget/PointerLocationView.java
index 4773e168fffa..3205b5aef281 100644
--- a/core/java/com/android/internal/widget/PointerLocationView.java
+++ b/core/java/com/android/internal/widget/PointerLocationView.java
@@ -20,12 +20,16 @@ import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.Paint.FontMetricsInt;
+import android.graphics.Path;
 import android.graphics.RectF;
+import android.graphics.Region;
 import android.hardware.input.InputManager;
 import android.hardware.input.InputManager.InputDeviceListener;
+import android.os.RemoteException;
 import android.os.SystemProperties;
 import android.util.Log;
 import android.util.Slog;
+import android.view.ISystemGestureExclusionListener;
 import android.view.InputDevice;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
@@ -34,6 +38,7 @@ import android.view.VelocityTracker;
 import android.view.View;
 import android.view.ViewConfiguration;
 import android.view.WindowInsets;
+import android.view.WindowManagerGlobal;
 import android.view.WindowManagerPolicyConstants.PointerEventListener;
 
 import java.util.ArrayList;
@@ -124,12 +129,16 @@ public class PointerLocationView extends View implements InputDeviceListener,
     private int mActivePointerId;
     private final ArrayList<PointerState> mPointers = new ArrayList<PointerState>();
     private final PointerCoords mTempCoords = new PointerCoords();
-    
+
+    private final Region mSystemGestureExclusion = new Region();
+    private final Path mSystemGestureExclusionPath = new Path();
+    private final Paint mSystemGestureExclusionPaint;
+
     private final VelocityTracker mVelocity;
     private final VelocityTracker mAltVelocity;
 
     private final FasterStringBuilder mText = new FasterStringBuilder();
-    
+
     private boolean mPrintCoords = true;
     
     public PointerLocationView(Context c) {
@@ -168,7 +177,11 @@ public class PointerLocationView extends View implements InputDeviceListener,
         mPathPaint.setARGB(255, 0, 96, 255);
         mPaint.setStyle(Paint.Style.STROKE);
         mPaint.setStrokeWidth(1);
-        
+
+        mSystemGestureExclusionPaint = new Paint();
+        mSystemGestureExclusionPaint.setARGB(25, 255, 0, 0);
+        mSystemGestureExclusionPaint.setStyle(Paint.Style.FILL_AND_STROKE);
+
         PointerState ps = new PointerState();
         mPointers.add(ps);
         mActivePointerId = 0;
@@ -236,6 +249,12 @@ public class PointerLocationView extends View implements InputDeviceListener,
 
         final int NP = mPointers.size();
 
+        if (!mSystemGestureExclusion.isEmpty()) {
+            mSystemGestureExclusionPath.reset();
+            mSystemGestureExclusion.getBoundaryPath(mSystemGestureExclusionPath);
+            canvas.drawPath(mSystemGestureExclusionPath, mSystemGestureExclusionPaint);
+        }
+
         // Labels
         if (mActivePointerId >= 0) {
             final PointerState ps = mPointers.get(mActivePointerId);
@@ -719,6 +738,12 @@ public class PointerLocationView extends View implements InputDeviceListener,
         super.onAttachedToWindow();
 
         mIm.registerInputDeviceListener(this, getHandler());
+        try {
+            WindowManagerGlobal.getWindowManagerService().registerSystemGestureExclusionListener(
+                    mSystemGestureExclusionListener, mContext.getDisplayId());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
         logInputDevices();
     }
 
@@ -727,6 +752,12 @@ public class PointerLocationView extends View implements InputDeviceListener,
         super.onDetachedFromWindow();
 
         mIm.unregisterInputDeviceListener(this);
+        try {
+            WindowManagerGlobal.getWindowManagerService().unregisterSystemGestureExclusionListener(
+                    mSystemGestureExclusionListener, mContext.getDisplayId());
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
     }
 
     @Override
@@ -876,4 +907,17 @@ public class PointerLocationView extends View implements InputDeviceListener,
             return oldLength;
         }
     }
+
+    private ISystemGestureExclusionListener mSystemGestureExclusionListener =
+            new ISystemGestureExclusionListener.Stub() {
+        @Override
+        public void onSystemGestureExclusionChanged(int displayId, Region systemGestureExclusion) {
+            Region exclusion = Region.obtain(systemGestureExclusion);
+            getHandler().post(() -> {
+                mSystemGestureExclusion.set(exclusion);
+                exclusion.recycle();
+                invalidate();
+            });
+        }
+    };
 }
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index db590308460b..b685a6327ae2 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -128,6 +128,7 @@ import static com.android.server.wm.WindowManagerService.logSurface;
 import static com.android.server.wm.WindowState.RESIZE_HANDLE_WIDTH_IN_DP;
 import static com.android.server.wm.WindowStateAnimator.DRAW_PENDING;
 import static com.android.server.wm.WindowStateAnimator.READY_TO_SHOW;
+import static com.android.server.wm.utils.RegionUtils.rectListToRegion;
 
 import android.animation.AnimationHandler;
 import android.annotation.CallSuper;
@@ -151,6 +152,7 @@ import android.os.Debug;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Process;
+import android.os.RemoteCallbackList;
 import android.os.RemoteException;
 import android.os.SystemClock;
 import android.os.Trace;
@@ -163,6 +165,7 @@ import android.view.Display;
 import android.view.DisplayCutout;
 import android.view.DisplayInfo;
 import android.view.Gravity;
+import android.view.ISystemGestureExclusionListener;
 import android.view.InputChannel;
 import android.view.InputDevice;
 import android.view.InputWindowHandle;
@@ -308,6 +311,10 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
     private DisplayRotation mDisplayRotation;
     DisplayFrames mDisplayFrames;
 
+    private final RemoteCallbackList<ISystemGestureExclusionListener>
+            mSystemGestureExclusionListeners = new RemoteCallbackList<>();
+    private final Region mSystemGestureExclusion = new Region();
+
     /**
      * For default display it contains real metrics, empty for others.
      * @see WindowManagerService#createWatermarkInTransaction()
@@ -2789,6 +2796,14 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
         mWallpaperController.dump(pw, "  ");
 
         pw.println();
+        pw.print("mSystemGestureExclusion=");
+        if (mSystemGestureExclusionListeners.getRegisteredCallbackCount() > 0) {
+            pw.println(mSystemGestureExclusion);
+        } else {
+            pw.println("<no lstnrs>");
+        }
+
+        pw.println();
         pw.println(prefix + "Application tokens in top down Z order:");
         for (int stackNdx = mTaskStackContainers.getChildCount() - 1; stackNdx >= 0; --stackNdx) {
             final TaskStack stack = mTaskStackContainers.getChildAt(stackNdx);
@@ -4914,6 +4929,100 @@ class DisplayContent extends WindowContainer<DisplayContent.DisplayChildWindowCo
     }
 
     /**
+     * Updates the display's system gesture exclusion.
+     *
+     * @return true, if the exclusion changed.
+     */
+    boolean updateSystemGestureExclusion() {
+        if (mSystemGestureExclusionListeners.getRegisteredCallbackCount() == 0) {
+            // No one's interested anyways.
+            return false;
+        }
+
+        final Region systemGestureExclusion = calculateSystemGestureExclusion();
+        try {
+            if (mSystemGestureExclusion.equals(systemGestureExclusion)) {
+                return false;
+            }
+            mSystemGestureExclusion.set(systemGestureExclusion);
+            for (int i = mSystemGestureExclusionListeners.beginBroadcast() - 1; i >= 0; --i) {
+                try {
+                    mSystemGestureExclusionListeners.getBroadcastItem(i)
+                            .onSystemGestureExclusionChanged(mDisplayId, systemGestureExclusion);
+                } catch (RemoteException e) {
+                    Slog.e(TAG, "Failed to notify SystemGestureExclusionListener", e);
+                }
+            }
+            mSystemGestureExclusionListeners.finishBroadcast();
+            return true;
+        } finally {
+            systemGestureExclusion.recycle();
+        }
+    }
+
+    @VisibleForTesting
+    Region calculateSystemGestureExclusion() {
+        final Region global = Region.obtain();
+        final Region touchableRegion = Region.obtain();
+        final Region local = Region.obtain();
+
+        // Traverse all windows bottom up to assemble the gesture exclusion rects.
+        // For each window, we only take the rects that fall within its touchable region.
+        forAllWindows(w -> {
+            if (w.cantReceiveTouchInput() || !w.isVisible()
+                    || (w.getAttrs().flags & FLAG_NOT_TOUCHABLE) != 0) {
+                return;
+            }
+            final boolean modal =
+                    (w.mAttrs.flags & (FLAG_NOT_TOUCH_MODAL | FLAG_NOT_FOCUSABLE)) == 0;
+
+            // Only keep the exclusion zones from the windows behind where the current window
+            // isn't touchable.
+            w.getTouchableRegion(touchableRegion);
+            global.op(touchableRegion, Op.DIFFERENCE);
+
+            rectListToRegion(w.getSystemGestureExclusion(), local);
+
+            // Transform to display coordinates
+            local.scale(w.mGlobalScale);
+            final Rect frame = w.getWindowFrames().mFrame;
+            local.translate(frame.left, frame.top);
+
+            // A window can only exclude system gestures where it is actually touchable
+            local.op(touchableRegion, Op.INTERSECT);
+
+            global.op(local, Op.UNION);
+        }, false /* topToBottom */);
+        local.recycle();
+        touchableRegion.recycle();
+        return global;
+    }
+
+    void registerSystemGestureExclusionListener(ISystemGestureExclusionListener listener) {
+        mSystemGestureExclusionListeners.register(listener);
+        final boolean changed;
+        if (mSystemGestureExclusionListeners.getRegisteredCallbackCount() == 1) {
+            changed = updateSystemGestureExclusion();
+        } else {
+            changed = false;
+        }
+
+        if (!changed) {
+            // If updateSystemGestureExclusion changed the exclusion, it will already have
+            // notified the listener. Otherwise, we'll do it here.
+            try {
+                listener.onSystemGestureExclusionChanged(mDisplayId, mSystemGestureExclusion);
+            } catch (RemoteException e) {
+                Slog.e(TAG, "Failed to notify SystemGestureExclusionListener during register", e);
+            }
+        }
+    }
+
+    void unregisterSystemGestureExclusionListener(ISystemGestureExclusionListener listener) {
+        mSystemGestureExclusionListeners.unregister(listener);
+    }
+
+    /**
      * Create a portal window handle for input. This window transports any touch to the display
      * indicated by {@link InputWindowHandle#portalToDisplayId} if the touch hits this window.
      *
diff --git a/services/core/java/com/android/server/wm/RootWindowContainer.java b/services/core/java/com/android/server/wm/RootWindowContainer.java
index 300cd17f33dd..1167d6f1d615 100644
--- a/services/core/java/com/android/server/wm/RootWindowContainer.java
+++ b/services/core/java/com/android/server/wm/RootWindowContainer.java
@@ -654,6 +654,7 @@ class RootWindowContainer extends WindowContainer<DisplayContent>
         // Finally update all input windows now that the window changes have stabilized.
         forAllDisplays(dc -> {
             dc.getInputMonitor().updateInputWindowsLw(true /*force*/);
+            dc.updateSystemGestureExclusion();
         });
 
         mWmService.setHoldScreenLocked(mHoldScreen);
diff --git a/services/core/java/com/android/server/wm/Session.java b/services/core/java/com/android/server/wm/Session.java
index dc8c7b79feef..9b634f959fca 100644
--- a/services/core/java/com/android/server/wm/Session.java
+++ b/services/core/java/com/android/server/wm/Session.java
@@ -57,6 +57,7 @@ import com.android.server.wm.WindowManagerService.H;
 
 import java.io.PrintWriter;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 import java.util.function.BiConsumer;
 
@@ -314,6 +315,16 @@ class Session extends IWindowSession.Stub implements IBinder.DeathRecipient {
         }
     }
 
+    @Override
+    public void reportSystemGestureExclusionChanged(IWindow window, List<Rect> exclusionRects) {
+        long ident = Binder.clearCallingIdentity();
+        try {
+            mService.reportSystemGestureExclusionChanged(this, window, exclusionRects);
+        } finally {
+            Binder.restoreCallingIdentity(ident);
+        }
+    }
+
     private void actionOnWallpaper(IBinder window,
             BiConsumer<WallpaperController, WindowState> action) {
         final WindowState windowState = mService.windowForClientLocked(this, window, true);
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index e3a8be5d52d4..a1e6eea39f86 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -202,6 +202,7 @@ import android.view.IOnKeyguardExitResult;
 import android.view.IPinnedStackListener;
 import android.view.IRecentsAnimationRunner;
 import android.view.IRotationWatcher;
+import android.view.ISystemGestureExclusionListener;
 import android.view.IWallpaperVisibilityListener;
 import android.view.IWindow;
 import android.view.IWindowId;
@@ -274,6 +275,7 @@ import java.text.DateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Date;
+import java.util.List;
 
 /** {@hide} */
 public class WindowManagerService extends IWindowManager.Stub
@@ -3788,6 +3790,42 @@ public class WindowManagerService extends IWindowManager.Stub
     }
 
     @Override
+    public void registerSystemGestureExclusionListener(ISystemGestureExclusionListener listener,
+            int displayId) {
+        synchronized (mGlobalLock) {
+            final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
+            if (displayContent == null) {
+                throw new IllegalArgumentException("Trying to register visibility event "
+                        + "for invalid display: " + displayId);
+            }
+            displayContent.registerSystemGestureExclusionListener(listener);
+        }
+    }
+
+    @Override
+    public void unregisterSystemGestureExclusionListener(ISystemGestureExclusionListener listener,
+            int displayId) {
+        synchronized (mGlobalLock) {
+            final DisplayContent displayContent = mRoot.getDisplayContent(displayId);
+            if (displayContent == null) {
+                throw new IllegalArgumentException("Trying to register visibility event "
+                        + "for invalid display: " + displayId);
+            }
+            displayContent.unregisterSystemGestureExclusionListener(listener);
+        }
+    }
+
+    void reportSystemGestureExclusionChanged(Session session, IWindow window,
+            List<Rect> exclusionRects) {
+        synchronized (mGlobalLock) {
+            final WindowState win = windowForClientLocked(session, window, true);
+            if (win.setSystemGestureExclusion(exclusionRects)) {
+                win.getDisplayContent().updateSystemGestureExclusion();
+            }
+        }
+    }
+
+    @Override
     public void registerDisplayFoldListener(IDisplayFoldListener listener) {
         mPolicy.registerDisplayFoldListener(listener);
     }
diff --git a/services/core/java/com/android/server/wm/WindowState.java b/services/core/java/com/android/server/wm/WindowState.java
index 20cca66d8a52..dd9e5901dc7a 100644
--- a/services/core/java/com/android/server/wm/WindowState.java
+++ b/services/core/java/com/android/server/wm/WindowState.java
@@ -205,6 +205,7 @@ import java.io.PrintWriter;
 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
 import java.util.Comparator;
+import java.util.List;
 import java.util.function.Predicate;
 
 /** A window in the window manager. */
@@ -363,6 +364,13 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
      */
     private final Rect mInsetFrame = new Rect();
 
+    /**
+     * List of rects where system gestures should be ignored.
+     *
+     * Coordinates are relative to the window's position.
+     */
+    private final List<Rect> mExclusionRects = new ArrayList<>();
+
     // If a window showing a wallpaper: the requested offset for the
     // wallpaper; if a wallpaper window: the currently applied offset.
     float mWallpaperX = -1;
@@ -612,6 +620,24 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
         }
     }
 
+    List<Rect> getSystemGestureExclusion() {
+        return mExclusionRects;
+    }
+
+    /**
+     * Sets the system gesture exclusion rects.
+     *
+     * @return {@code true} if anything changed
+     */
+    boolean setSystemGestureExclusion(List<Rect> exclusionRects) {
+        if (mExclusionRects.equals(exclusionRects)) {
+            return false;
+        }
+        mExclusionRects.clear();
+        mExclusionRects.addAll(exclusionRects);
+        return true;
+    }
+
     interface PowerManagerWrapper {
         void wakeUp(long time, @WakeReason int reason, String details);
 
diff --git a/services/core/java/com/android/server/wm/utils/RegionUtils.java b/services/core/java/com/android/server/wm/utils/RegionUtils.java
new file mode 100644
index 000000000000..1458440f7b81
--- /dev/null
+++ b/services/core/java/com/android/server/wm/utils/RegionUtils.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wm.utils;
+
+import android.graphics.Rect;
+import android.graphics.Region;
+
+import java.util.List;
+
+/**
+ * Utility methods to handle Regions.
+ */
+public class RegionUtils {
+
+    private RegionUtils() {}
+
+
+    /**
+     * Converts a list of rects into a {@code Region}.
+     *
+     * @param rects the list of rects to convert
+     * @param outRegion the Region to set to the list of rects
+     */
+    public static void rectListToRegion(List<Rect> rects, Region outRegion) {
+        outRegion.setEmpty();
+        final int n = rects.size();
+        for (int i = 0; i < n; i++) {
+            outRegion.union(rects.get(i));
+        }
+    }
+}
diff --git a/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java b/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
index b26aa050870a..51dac6fdd1eb 100644
--- a/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
@@ -25,6 +25,8 @@ import static android.view.Display.DEFAULT_DISPLAY;
 import static android.view.DisplayCutout.BOUNDS_POSITION_LEFT;
 import static android.view.DisplayCutout.BOUNDS_POSITION_TOP;
 import static android.view.DisplayCutout.fromBoundingRect;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_INSET_DECOR;
+import static android.view.WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG;
 import static android.view.WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
@@ -57,12 +59,15 @@ import android.annotation.SuppressLint;
 import android.app.WindowConfiguration;
 import android.content.res.Configuration;
 import android.graphics.Rect;
+import android.graphics.Region;
 import android.metrics.LogMaker;
 import android.os.SystemClock;
 import android.platform.test.annotations.Presubmit;
 import android.util.DisplayMetrics;
+import android.util.MutableBoolean;
 import android.view.DisplayCutout;
 import android.view.Gravity;
+import android.view.ISystemGestureExclusionListener;
 import android.view.MotionEvent;
 import android.view.Surface;
 import android.view.ViewRootImpl;
@@ -673,6 +678,60 @@ public class DisplayContentTests extends WindowTestsBase {
     }
 
     @Test
+    public void testUpdateSystemGestureExclusion() throws Exception {
+        final DisplayContent dc = createNewDisplay();
+        final WindowState win = createWindow(null, TYPE_BASE_APPLICATION, dc, "win");
+        win.getAttrs().flags |= FLAG_LAYOUT_IN_SCREEN | FLAG_LAYOUT_INSET_DECOR;
+        win.setSystemGestureExclusion(Collections.singletonList(new Rect(10, 20, 30, 40)));
+
+        dc.setLayoutNeeded();
+        dc.performLayout(true /* initial */, false /* updateImeWindows */);
+
+        win.setHasSurface(true);
+        dc.updateSystemGestureExclusion();
+
+        final MutableBoolean invoked = new MutableBoolean(false);
+        final ISystemGestureExclusionListener.Stub verifier =
+                new ISystemGestureExclusionListener.Stub() {
+            @Override
+            public void onSystemGestureExclusionChanged(int displayId, Region actual) {
+                Region expected = Region.obtain();
+                expected.set(10, 20, 30, 40);
+                assertEquals(expected, actual);
+                invoked.value = true;
+            }
+        };
+        try {
+            dc.registerSystemGestureExclusionListener(verifier);
+        } finally {
+            dc.unregisterSystemGestureExclusionListener(verifier);
+        }
+        assertTrue("SystemGestureExclusionListener was not invoked", invoked.value);
+    }
+
+    @Test
+    public void testCalculateSystemGestureExclusion() throws Exception {
+        final DisplayContent dc = createNewDisplay();
+        final WindowState win = createWindow(null, TYPE_BASE_APPLICATION, dc, "win");
+        win.getAttrs().flags |= FLAG_LAYOUT_IN_SCREEN | FLAG_LAYOUT_INSET_DECOR;
+        win.setSystemGestureExclusion(Collections.singletonList(new Rect(10, 20, 30, 40)));
+
+        final WindowState win2 = createWindow(null, TYPE_APPLICATION, dc, "win2");
+        win2.getAttrs().flags |= FLAG_LAYOUT_IN_SCREEN | FLAG_LAYOUT_INSET_DECOR;
+        win2.setSystemGestureExclusion(Collections.singletonList(new Rect(20, 30, 40, 50)));
+
+        dc.setLayoutNeeded();
+        dc.performLayout(true /* initial */, false /* updateImeWindows */);
+
+        win.setHasSurface(true);
+        win2.setHasSurface(true);
+
+        final Region expected = Region.obtain();
+        expected.set(20, 30, 40, 50);
+        assertEquals(expected, dc.calculateSystemGestureExclusion());
+    }
+
+    @Test
     public void testOrientationChangeLogging() {
         MetricsLogger mockLogger = mock(MetricsLogger.class);
         Configuration oldConfig = new Configuration();