Synchronize window config updates (1/n)

When updating Configuration on the client side, check if this should
trigger onDisplayChanged.

Bug: 260873529
Test: atest WmTests:WindowConfigurationTests
Test: atest FrameworksCoreTests:WindowContextInfoChangeItemTest
Change-Id: I8baa0f43d6bd00a93910fed4aec2d53f2044e0c7

16 files changed, 366 insertions, 17 deletions

diff --git a/core/api/test-current.txt b/core/api/test-current.txt
index 773d720d73fb..6210715440fb 100644
--- a/core/api/test-current.txt
+++ b/core/api/test-current.txt
@@ -496,15 +496,15 @@ package android.app {
     method public int compareTo(android.app.WindowConfiguration);
     method public int describeContents();
     method public int getActivityType();
-    method public android.graphics.Rect getAppBounds();
-    method public android.graphics.Rect getBounds();
+    method @Nullable public android.graphics.Rect getAppBounds();
+    method @NonNull public android.graphics.Rect getBounds();
     method @NonNull public android.graphics.Rect getMaxBounds();
     method public int getRotation();
     method public int getWindowingMode();
     method public static boolean isFloating(int);
     method public void setActivityType(int);
-    method public void setAppBounds(android.graphics.Rect);
-    method public void setBounds(android.graphics.Rect);
+    method public void setAppBounds(@Nullable android.graphics.Rect);
+    method public void setBounds(@Nullable android.graphics.Rect);
     method public void setMaxBounds(@Nullable android.graphics.Rect);
     method public void setRotation(int);
     method public void setTo(android.app.WindowConfiguration);
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index cc716ecfdafa..3dd69e46a7d9 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -3580,6 +3580,12 @@ public final class ActivityThread extends ClientTransactionHandler
         return mActivities.get(token);
     }
 
+    @Nullable
+    @Override
+    public Context getWindowContext(@NonNull IBinder clientToken) {
+        return WindowTokenClientController.getInstance().getWindowContext(clientToken);
+    }
+
     @VisibleForTesting(visibility = PACKAGE)
     public Configuration getConfiguration() {
         return mConfigurationController.getConfiguration();
diff --git a/core/java/android/app/ClientTransactionHandler.java b/core/java/android/app/ClientTransactionHandler.java
index 6753cb884ea7..98020ff2d173 100644
--- a/core/java/android/app/ClientTransactionHandler.java
+++ b/core/java/android/app/ClientTransactionHandler.java
@@ -16,11 +16,13 @@
 package android.app;
 
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.app.ActivityThread.ActivityClientRecord;
 import android.app.servertransaction.ClientTransaction;
 import android.app.servertransaction.ClientTransactionItem;
 import android.app.servertransaction.PendingTransactionActions;
 import android.app.servertransaction.TransactionExecutor;
+import android.content.Context;
 import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.res.Configuration;
@@ -28,6 +30,7 @@ import android.os.IBinder;
 import android.util.MergedConfiguration;
 import android.view.SurfaceControl;
 import android.window.SplashScreenView.SplashScreenViewParcelable;
+import android.window.WindowContext;
 import android.window.WindowContextInfo;
 
 import com.android.internal.annotations.VisibleForTesting;
@@ -85,6 +88,10 @@ public abstract class ClientTransactionHandler {
     /** Get activity instance for the token. */
     public abstract Activity getActivity(IBinder token);
 
+    /** Gets the {@link WindowContext} instance for the token. */
+    @Nullable
+    public abstract Context getWindowContext(@NonNull IBinder clientToken);
+
     // Prepare phase related logic and handlers. Methods that inform about about pending changes or
     // do other internal bookkeeping.
 
diff --git a/core/java/android/app/WindowConfiguration.java b/core/java/android/app/WindowConfiguration.java
index 5b955031a098..e3055e5042c6 100644
--- a/core/java/android/app/WindowConfiguration.java
+++ b/core/java/android/app/WindowConfiguration.java
@@ -36,6 +36,7 @@ import android.os.Parcelable;
 import android.util.proto.ProtoInputStream;
 import android.util.proto.ProtoOutputStream;
 import android.util.proto.WireTypeMismatchException;
+import android.view.Display;
 import android.view.DisplayInfo;
 import android.view.Surface;
 import android.view.WindowManager;
@@ -66,6 +67,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
      * the display level. Lower levels can override these values to provide custom bounds to enforce
      * features such as a max aspect ratio.
      */
+    @Nullable
     private Rect mAppBounds;
 
     /**
@@ -269,7 +271,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
      * Sets the bounds to the provided {@link Rect}.
      * @param rect the new bounds value.
      */
-    public void setBounds(Rect rect) {
+    public void setBounds(@Nullable Rect rect) {
         if (rect == null) {
             mBounds.setEmpty();
             return;
@@ -283,7 +285,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
      * @param rect The rect value to set {@link #mAppBounds} to.
      * @see #getAppBounds()
      */
-    public void setAppBounds(Rect rect) {
+    public void setAppBounds(@Nullable Rect rect) {
         if (rect == null) {
             mAppBounds = null;
             return;
@@ -356,11 +358,13 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     }
 
     /** @see #setAppBounds(Rect) */
+    @Nullable
     public Rect getAppBounds() {
         return mAppBounds;
     }
 
     /** @see #setBounds(Rect) */
+    @NonNull
     public Rect getBounds() {
         return mBounds;
     }
@@ -905,6 +909,23 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
         return activityType != ACTIVITY_TYPE_ASSISTANT && activityType != ACTIVITY_TYPE_DREAM;
     }
 
+    /**
+     * Checks if the two {@link Configuration}s are equal to each other for the fields that are read
+     * by {@link Display}.
+     * @hide
+     */
+    public static boolean areConfigurationsEqualForDisplay(@NonNull Configuration newConfig,
+            @NonNull Configuration oldConfig) {
+        // Only report different if max bounds and display rotation is changed, so that it will not
+        // report on Task resizing.
+        if (!newConfig.windowConfiguration.getMaxBounds().equals(
+                oldConfig.windowConfiguration.getMaxBounds())) {
+            return false;
+        }
+        return newConfig.windowConfiguration.getDisplayRotation()
+                == oldConfig.windowConfiguration.getDisplayRotation();
+    }
+
     /** @hide */
     public static String windowingModeToString(@WindowingMode int windowingMode) {
         switch (windowingMode) {
diff --git a/core/java/android/app/servertransaction/ActivityConfigurationChangeItem.java b/core/java/android/app/servertransaction/ActivityConfigurationChangeItem.java
index 1c490be08381..e40925441f0f 100644
--- a/core/java/android/app/servertransaction/ActivityConfigurationChangeItem.java
+++ b/core/java/android/app/servertransaction/ActivityConfigurationChangeItem.java
@@ -23,6 +23,7 @@ import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.ActivityThread.ActivityClientRecord;
 import android.app.ClientTransactionHandler;
+import android.content.Context;
 import android.content.res.CompatibilityInfo;
 import android.content.res.Configuration;
 import android.os.IBinder;
@@ -40,7 +41,7 @@ public class ActivityConfigurationChangeItem extends ActivityTransactionItem {
     private Configuration mConfiguration;
 
     @Override
-    public void preExecute(android.app.ClientTransactionHandler client, IBinder token) {
+    public void preExecute(@NonNull ClientTransactionHandler client, @Nullable IBinder token) {
         CompatibilityInfo.applyOverrideScaleIfNeeded(mConfiguration);
         // Notify the client of an upcoming change in the token configuration. This ensures that
         // batches of config change items only process the newest configuration.
@@ -48,14 +49,21 @@ public class ActivityConfigurationChangeItem extends ActivityTransactionItem {
     }
 
     @Override
-    public void execute(ClientTransactionHandler client, ActivityClientRecord r,
-            PendingTransactionActions pendingActions) {
+    public void execute(@NonNull ClientTransactionHandler client, @Nullable ActivityClientRecord r,
+            @NonNull PendingTransactionActions pendingActions) {
         // TODO(lifecycler): detect if PIP or multi-window mode changed and report it here.
         Trace.traceBegin(TRACE_TAG_ACTIVITY_MANAGER, "activityConfigChanged");
         client.handleActivityConfigurationChanged(r, mConfiguration, INVALID_DISPLAY);
         Trace.traceEnd(TRACE_TAG_ACTIVITY_MANAGER);
     }
 
+    @Nullable
+    @Override
+    public Context getContextToUpdate(@NonNull ClientTransactionHandler client,
+            @Nullable IBinder token) {
+        // TODO(b/260873529): Update ClientTransaction to bundle multiple activity config updates.
+        return client.getActivity(token);
+    }
 
     // ObjectPoolItem implementation
 
diff --git a/core/java/android/app/servertransaction/ClientTransactionItem.java b/core/java/android/app/servertransaction/ClientTransactionItem.java
index b159f336cd85..fe75d89e1257 100644
--- a/core/java/android/app/servertransaction/ClientTransactionItem.java
+++ b/core/java/android/app/servertransaction/ClientTransactionItem.java
@@ -19,6 +19,11 @@ package android.app.servertransaction;
 import static android.app.servertransaction.ActivityLifecycleItem.LifecycleState;
 import static android.app.servertransaction.ActivityLifecycleItem.UNDEFINED;
 
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.app.ClientTransactionHandler;
+import android.content.Context;
+import android.os.IBinder;
 import android.os.Parcelable;
 
 /**
@@ -42,6 +47,16 @@ public abstract class ClientTransactionItem implements BaseClientRequest, Parcel
         return true;
     }
 
+    /**
+     * If this {@link ClientTransactionItem} is updating configuration, returns the {@link Context}
+     * it is updating; otherwise, returns {@code null}.
+     */
+    @Nullable
+    public Context getContextToUpdate(@NonNull ClientTransactionHandler client,
+            @NonNull IBinder token) {
+        return null;
+    }
+
     // Parcelable
 
     @Override
diff --git a/core/java/android/app/servertransaction/ConfigurationChangeItem.java b/core/java/android/app/servertransaction/ConfigurationChangeItem.java
index a563bbc9c70d..f72e2e04deca 100644
--- a/core/java/android/app/servertransaction/ConfigurationChangeItem.java
+++ b/core/java/android/app/servertransaction/ConfigurationChangeItem.java
@@ -16,8 +16,11 @@
 
 package android.app.servertransaction;
 
+import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.app.ActivityThread;
 import android.app.ClientTransactionHandler;
+import android.content.Context;
 import android.content.res.CompatibilityInfo;
 import android.content.res.Configuration;
 import android.os.IBinder;
@@ -35,24 +38,30 @@ public class ConfigurationChangeItem extends ClientTransactionItem {
     private int mDeviceId;
 
     @Override
-    public void preExecute(android.app.ClientTransactionHandler client, IBinder token) {
+    public void preExecute(@NonNull ClientTransactionHandler client, @Nullable IBinder token) {
         CompatibilityInfo.applyOverrideScaleIfNeeded(mConfiguration);
         client.updatePendingConfiguration(mConfiguration);
     }
 
     @Override
-    public void execute(ClientTransactionHandler client, IBinder token,
-            PendingTransactionActions pendingActions) {
+    public void execute(@NonNull ClientTransactionHandler client, @Nullable IBinder token,
+            @NonNull PendingTransactionActions pendingActions) {
         client.handleConfigurationChanged(mConfiguration, mDeviceId);
     }
 
+    @Nullable
+    @Override
+    public Context getContextToUpdate(@NonNull ClientTransactionHandler client,
+            @Nullable IBinder token) {
+        return ActivityThread.currentApplication();
+    }
 
     // ObjectPoolItem implementation
 
     private ConfigurationChangeItem() {}
 
     /** Obtain an instance initialized with provided params. */
-    public static ConfigurationChangeItem obtain(Configuration config, int deviceId) {
+    public static ConfigurationChangeItem obtain(@NonNull Configuration config, int deviceId) {
         ConfigurationChangeItem instance = ObjectPool.obtain(ConfigurationChangeItem.class);
         if (instance == null) {
             instance = new ConfigurationChangeItem();
diff --git a/core/java/android/app/servertransaction/TransactionExecutor.java b/core/java/android/app/servertransaction/TransactionExecutor.java
index bfab61f3ae90..09a9ab326ef7 100644
--- a/core/java/android/app/servertransaction/TransactionExecutor.java
+++ b/core/java/android/app/servertransaction/TransactionExecutor.java
@@ -16,6 +16,7 @@
 
 package android.app.servertransaction;
 
+import static android.app.WindowConfiguration.areConfigurationsEqualForDisplay;
 import static android.app.servertransaction.ActivityLifecycleItem.ON_CREATE;
 import static android.app.servertransaction.ActivityLifecycleItem.ON_DESTROY;
 import static android.app.servertransaction.ActivityLifecycleItem.ON_PAUSE;
@@ -30,10 +31,16 @@ import static android.app.servertransaction.TransactionExecutorHelper.lastCallba
 import static android.app.servertransaction.TransactionExecutorHelper.tId;
 import static android.app.servertransaction.TransactionExecutorHelper.transactionToString;
 
+import static com.android.window.flags.Flags.syncWindowConfigUpdateFlag;
+
+import android.annotation.NonNull;
 import android.app.ActivityThread.ActivityClientRecord;
 import android.app.ClientTransactionHandler;
 import android.content.Context;
+import android.content.res.Configuration;
 import android.os.IBinder;
+import android.os.Process;
+import android.util.ArraySet;
 import android.util.IntArray;
 import android.util.Slog;
 
@@ -51,12 +58,12 @@ public class TransactionExecutor {
     private static final boolean DEBUG_RESOLVER = false;
     private static final String TAG = "TransactionExecutor";
 
-    private ClientTransactionHandler mTransactionHandler;
-    private PendingTransactionActions mPendingActions = new PendingTransactionActions();
-    private TransactionExecutorHelper mHelper = new TransactionExecutorHelper();
+    private final ClientTransactionHandler mTransactionHandler;
+    private final PendingTransactionActions mPendingActions = new PendingTransactionActions();
+    private final TransactionExecutorHelper mHelper = new TransactionExecutorHelper();
 
     /** Initialize an instance with transaction handler, that will execute all requested actions. */
-    public TransactionExecutor(ClientTransactionHandler clientTransactionHandler) {
+    public TransactionExecutor(@NonNull ClientTransactionHandler clientTransactionHandler) {
         mTransactionHandler = clientTransactionHandler;
     }
 
@@ -122,6 +129,9 @@ public class TransactionExecutor {
         // Index of the last callback that requests some post-execution state.
         final int lastCallbackRequestingState = lastCallbackRequestingState(transaction);
 
+        // Keep track of display ids whose Configuration got updated with this transaction.
+        ArraySet<Integer> configUpdatedDisplays = null;
+
         final int size = callbacks.size();
         for (int i = 0; i < size; ++i) {
             final ClientTransactionItem item = callbacks.get(i);
@@ -136,7 +146,29 @@ public class TransactionExecutor {
                 }
             }
 
+            // Can't read flag from isolated process.
+            final boolean isSyncWindowConfigUpdateFlagEnabled = !Process.isIsolated()
+                    && syncWindowConfigUpdateFlag();
+            final Context configUpdatedContext = isSyncWindowConfigUpdateFlagEnabled
+                    ? item.getContextToUpdate(mTransactionHandler, token)
+                    : null;
+            final Configuration preExecutedConfig = configUpdatedContext != null
+                    ? new Configuration(configUpdatedContext.getResources().getConfiguration())
+                    : null;
+
             item.execute(mTransactionHandler, token, mPendingActions);
+
+            if (configUpdatedContext != null) {
+                final Configuration postExecutedConfig = configUpdatedContext.getResources()
+                        .getConfiguration();
+                if (!areConfigurationsEqualForDisplay(postExecutedConfig, preExecutedConfig)) {
+                    if (configUpdatedDisplays == null) {
+                        configUpdatedDisplays = new ArraySet<>();
+                    }
+                    configUpdatedDisplays.add(configUpdatedContext.getDisplayId());
+                }
+            }
+
             item.postExecute(mTransactionHandler, token, mPendingActions);
             if (r == null) {
                 // Launch activity request will create an activity record.
@@ -150,6 +182,13 @@ public class TransactionExecutor {
                 cycleToPath(r, postExecutionState, shouldExcludeLastTransition, transaction);
             }
         }
+
+        if (configUpdatedDisplays != null) {
+            final int displayCount = configUpdatedDisplays.size();
+            for (int i = 0; i < displayCount; i++) {
+                // TODO(b/260873529): trigger onDisplayChanged.
+            }
+        }
     }
 
     /** Transition to the final state if requested by the transaction. */
diff --git a/core/java/android/app/servertransaction/WindowContextInfoChangeItem.java b/core/java/android/app/servertransaction/WindowContextInfoChangeItem.java
index 74721d555081..99824b000b70 100644
--- a/core/java/android/app/servertransaction/WindowContextInfoChangeItem.java
+++ b/core/java/android/app/servertransaction/WindowContextInfoChangeItem.java
@@ -21,6 +21,7 @@ import static java.util.Objects.requireNonNull;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.app.ClientTransactionHandler;
+import android.content.Context;
 import android.content.res.Configuration;
 import android.os.IBinder;
 import android.os.Parcel;
@@ -45,6 +46,13 @@ public class WindowContextInfoChangeItem extends ClientTransactionItem {
         client.handleWindowContextInfoChanged(mClientToken, mInfo);
     }
 
+    @Nullable
+    @Override
+    public Context getContextToUpdate(@NonNull ClientTransactionHandler client,
+            @Nullable IBinder token) {
+        return client.getWindowContext(mClientToken);
+    }
+
     // ObjectPoolItem implementation
 
     private WindowContextInfoChangeItem() {}
diff --git a/core/java/android/window/WindowTokenClient.java b/core/java/android/window/WindowTokenClient.java
index c1d1b2754895..f4f1b3b9b27b 100644
--- a/core/java/android/window/WindowTokenClient.java
+++ b/core/java/android/window/WindowTokenClient.java
@@ -22,6 +22,7 @@ import static android.window.ConfigurationHelper.shouldUpdateResources;
 import android.annotation.AnyThread;
 import android.annotation.MainThread;
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.app.ActivityThread;
 import android.app.ResourcesManager;
 import android.content.Context;
@@ -91,6 +92,15 @@ public class WindowTokenClient extends Binder {
     }
 
     /**
+     * Gets the {@link Context} that this {@link WindowTokenClient} is attached through
+     * {@link #attachContext(Context)}.
+     */
+    @Nullable
+    public Context getContext() {
+        return mContextRef != null ? mContextRef.get() : null;
+    }
+
+    /**
      * Called when {@link Configuration} updates from the server side receive.
      *
      * @param newConfig the updated {@link Configuration}
diff --git a/core/java/android/window/WindowTokenClientController.java b/core/java/android/window/WindowTokenClientController.java
index 10f6d5e7abaa..abf7bb15b3d8 100644
--- a/core/java/android/window/WindowTokenClientController.java
+++ b/core/java/android/window/WindowTokenClientController.java
@@ -82,6 +82,16 @@ public class WindowTokenClientController {
 
     private WindowTokenClientController() {}
 
+    /** Gets the {@link WindowContext} instance for the token. */
+    @Nullable
+    public Context getWindowContext(@NonNull IBinder clientToken) {
+        final WindowTokenClient windowTokenClient;
+        synchronized (mLock) {
+            windowTokenClient = mWindowTokenClientMap.get(clientToken);
+        }
+        return windowTokenClient != null ? windowTokenClient.getContext() : null;
+    }
+
     /**
      * Attaches a {@link WindowTokenClient} to a {@link com.android.server.wm.DisplayArea}.
      *
diff --git a/core/tests/coretests/src/android/app/servertransaction/ActivityConfigurationChangeItemTest.java b/core/tests/coretests/src/android/app/servertransaction/ActivityConfigurationChangeItemTest.java
new file mode 100644
index 000000000000..1560c0c2c195
--- /dev/null
+++ b/core/tests/coretests/src/android/app/servertransaction/ActivityConfigurationChangeItemTest.java
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2023 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.app.servertransaction;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.doReturn;
+
+import android.app.Activity;
+import android.app.ClientTransactionHandler;
+import android.content.Context;
+import android.content.res.Configuration;
+import android.os.IBinder;
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/**
+ * Tests for {@link ActivityConfigurationChangeItem}.
+ *
+ * Build/Install/Run:
+ *  atest FrameworksCoreTests:ActivityConfigurationChangeItemTest
+ */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+@Presubmit
+public class ActivityConfigurationChangeItemTest {
+
+    @Mock
+    private ClientTransactionHandler mHandler;
+    @Mock
+    private IBinder mToken;
+    @Mock
+    private Activity mActivity;
+    // Can't mock final class.
+    private final Configuration mConfiguration = new Configuration();
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+    }
+
+    @Test
+    public void testGetContextToUpdate() {
+        doReturn(mActivity).when(mHandler).getActivity(mToken);
+
+        final ActivityConfigurationChangeItem item = ActivityConfigurationChangeItem
+                .obtain(mConfiguration);
+        final Context context = item.getContextToUpdate(mHandler, mToken);
+
+        assertEquals(mActivity, context);
+    }
+}
diff --git a/core/tests/coretests/src/android/app/servertransaction/ConfigurationChangeItemTest.java b/core/tests/coretests/src/android/app/servertransaction/ConfigurationChangeItemTest.java
new file mode 100644
index 000000000000..3926cfb14194
--- /dev/null
+++ b/core/tests/coretests/src/android/app/servertransaction/ConfigurationChangeItemTest.java
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2023 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.app.servertransaction;
+
+import static android.content.Context.DEVICE_ID_DEFAULT;
+
+import static org.junit.Assert.assertEquals;
+
+import android.app.ActivityThread;
+import android.app.ClientTransactionHandler;
+import android.content.Context;
+import android.content.res.Configuration;
+import android.os.IBinder;
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/**
+ * Tests for {@link ConfigurationChangeItem}.
+ *
+ * Build/Install/Run:
+ *  atest FrameworksCoreTests:ConfigurationChangeItemTest
+ */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+@Presubmit
+public class ConfigurationChangeItemTest {
+
+    @Mock
+    private ClientTransactionHandler mHandler;
+    @Mock
+    private IBinder mToken;
+    // Can't mock final class.
+    private final Configuration mConfiguration = new Configuration();
+
+    @Before
+    public void setup() {
+        MockitoAnnotations.initMocks(this);
+    }
+
+    @Test
+    public void testGetContextToUpdate() {
+        final ConfigurationChangeItem item = ConfigurationChangeItem
+                .obtain(mConfiguration, DEVICE_ID_DEFAULT);
+        final Context context = item.getContextToUpdate(mHandler, mToken);
+
+        assertEquals(ActivityThread.currentApplication(), context);
+    }
+}
diff --git a/core/tests/coretests/src/android/app/servertransaction/WindowContextInfoChangeItemTest.java b/core/tests/coretests/src/android/app/servertransaction/WindowContextInfoChangeItemTest.java
index 37a517e87c74..db76d26b063e 100644
--- a/core/tests/coretests/src/android/app/servertransaction/WindowContextInfoChangeItemTest.java
+++ b/core/tests/coretests/src/android/app/servertransaction/WindowContextInfoChangeItemTest.java
@@ -18,15 +18,24 @@ package android.app.servertransaction;
 
 import static android.view.Display.DEFAULT_DISPLAY;
 
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.verify;
 
 import android.app.ClientTransactionHandler;
+import android.content.Context;
 import android.content.res.Configuration;
 import android.os.IBinder;
+import android.platform.test.annotations.Presubmit;
+import android.window.WindowContext;
 import android.window.WindowContextInfo;
 
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
+
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
@@ -36,6 +45,9 @@ import org.mockito.MockitoAnnotations;
  * Build/Install/Run:
  *  atest FrameworksCoreTests:WindowContextInfoChangeItemTest
  */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+@Presubmit
 public class WindowContextInfoChangeItemTest {
 
     @Mock
@@ -46,6 +58,8 @@ public class WindowContextInfoChangeItemTest {
     private PendingTransactionActions mPendingActions;
     @Mock
     private IBinder mClientToken;
+    @Mock
+    private WindowContext mWindowContext;
     // Can't mock final class.
     private final Configuration mConfiguration = new Configuration();
 
@@ -63,4 +77,15 @@ public class WindowContextInfoChangeItemTest {
         verify(mHandler).handleWindowContextInfoChanged(mClientToken,
                 new WindowContextInfo(mConfiguration, DEFAULT_DISPLAY));
     }
+
+    @Test
+    public void testGetContextToUpdate() {
+        doReturn(mWindowContext).when(mHandler).getWindowContext(mClientToken);
+
+        final WindowContextInfoChangeItem item = WindowContextInfoChangeItem
+                .obtain(mClientToken, mConfiguration, DEFAULT_DISPLAY);
+        final Context context = item.getContextToUpdate(mHandler, mToken);
+
+        assertEquals(mWindowContext, context);
+    }
 }
diff --git a/core/tests/coretests/src/android/app/servertransaction/WindowContextWindowRemovalItemTest.java b/core/tests/coretests/src/android/app/servertransaction/WindowContextWindowRemovalItemTest.java
index 2c83c70e9ae2..17e0ebc1edbc 100644
--- a/core/tests/coretests/src/android/app/servertransaction/WindowContextWindowRemovalItemTest.java
+++ b/core/tests/coretests/src/android/app/servertransaction/WindowContextWindowRemovalItemTest.java
@@ -20,9 +20,14 @@ import static org.mockito.Mockito.verify;
 
 import android.app.ClientTransactionHandler;
 import android.os.IBinder;
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.filters.SmallTest;
+import androidx.test.runner.AndroidJUnit4;
 
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
@@ -32,6 +37,9 @@ import org.mockito.MockitoAnnotations;
  * Build/Install/Run:
  *  atest FrameworksCoreTests:WindowContextWindowRemovalItemTest
  */
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+@Presubmit
 public class WindowContextWindowRemovalItemTest {
 
     @Mock
diff --git a/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java b/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
index 45cd6a200d01..38aac7cfee22 100644
--- a/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
@@ -30,6 +30,7 @@ import static android.app.WindowConfiguration.WINDOW_CONFIG_BOUNDS;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_MAX_BOUNDS;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_ROTATION;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_WINDOWING_MODE;
+import static android.app.WindowConfiguration.areConfigurationsEqualForDisplay;
 import static android.content.pm.ActivityInfo.CONFIG_WINDOW_CONFIGURATION;
 import static android.view.Surface.ROTATION_270;
 
@@ -269,4 +270,43 @@ public class WindowConfigurationTests extends WindowTestsBase {
         config.setTo(other, justWindowingMode);
         assertEquals(WINDOWING_MODE_UNDEFINED, config.getWindowingMode());
     }
+
+    @Test
+    public void testAreConfigurationsEqualForDisplay() {
+        final Configuration config0 = new Configuration();
+        final Configuration config1 = new Configuration();
+
+        assertTrue(areConfigurationsEqualForDisplay(config0, config1));
+
+        // Only compare fields read in Display.
+        config0.densityDpi = 1;
+        config1.densityDpi = 2;
+
+        assertTrue(areConfigurationsEqualForDisplay(config0, config1));
+
+        // MaxBounds
+        final Rect bounds0 = new Rect(0, 0, 500, 1000);
+        final Rect bounds1 = new Rect(0, 0, 1000, 500);
+
+        config0.windowConfiguration.setMaxBounds(bounds0);
+        config1.windowConfiguration.setMaxBounds(bounds1);
+
+        assertFalse(areConfigurationsEqualForDisplay(config0, config1));
+
+        config0.windowConfiguration.setMaxBounds(null);
+        config1.windowConfiguration.setMaxBounds(null);
+
+        assertTrue(areConfigurationsEqualForDisplay(config0, config1));
+
+        // DisplayRotation
+        config0.windowConfiguration.setDisplayRotation(0);
+        config1.windowConfiguration.setDisplayRotation(1);
+
+        assertFalse(areConfigurationsEqualForDisplay(config0, config1));
+
+        config0.windowConfiguration.setDisplayRotation(2);
+        config1.windowConfiguration.setDisplayRotation(2);
+
+        assertTrue(areConfigurationsEqualForDisplay(config0, config1));
+    }
 }