Merge "Add a way to disable auto rotation for immersive apps" into tm-qpr-dev
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index f7187c4..2f5efd1 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -5213,6 +5213,14 @@
          having a separating hinge. -->
     <bool name="config_isDisplayHingeAlwaysSeparating">false</bool>
 
+    <!-- Whether enabling rotation compat policy for immersive apps that prevents auto rotation
+         into non-optimal screen orientation while in fullscreen. This is needed because immersive
+         apps, such as games, are often not optimized for all orientations and can have a poor UX
+         when rotated. Additionally, some games rely on sensors for the gameplay so users can
+         trigger such rotations accidentally when auto rotation is on.
+         Applicable only if ignoreOrientationRequest is enabled. -->
+    <bool name="config_letterboxIsDisplayRotationImmersiveAppCompatPolicyEnabled">false</bool>
+
     <!-- Aspect ratio of letterboxing for fixed orientation. Values <= 1.0 will be ignored.
          Note: Activity min/max aspect ratio restrictions will still be respected.
          Therefore this override can control the maximum screen area that can be occupied by
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 368ef96..41281fa 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -4441,6 +4441,7 @@
   <java-symbol type="dimen" name="controls_thumbnail_image_max_height" />
   <java-symbol type="dimen" name="controls_thumbnail_image_max_width" />
 
+  <java-symbol type="bool" name="config_letterboxIsDisplayRotationImmersiveAppCompatPolicyEnabled" />
   <java-symbol type="dimen" name="config_fixedOrientationLetterboxAspectRatio" />
   <java-symbol type="dimen" name="config_letterboxBackgroundWallpaperBlurRadius" />
   <java-symbol type="integer" name="config_letterboxActivityCornersRadius" />
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java b/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
index 8ee893c..359da13 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
@@ -249,7 +249,8 @@
     }
 
     public void setRotationLockedAtAngle(int rotationSuggestion) {
-        RotationPolicy.setRotationLockAtAngle(mContext, true, rotationSuggestion);
+        RotationPolicy.setRotationLockAtAngle(mContext, /* enabled= */ isRotationLocked(),
+                /* rotation= */ rotationSuggestion);
     }
 
     public boolean isRotationLocked() {
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 36f86d1..75d84ea 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -5948,6 +5948,7 @@
         }
     }
 
+    @Nullable
     ActivityRecord topRunningActivity() {
         return topRunningActivity(false /* considerKeyguardState */);
     }
diff --git a/services/core/java/com/android/server/wm/DisplayRotation.java b/services/core/java/com/android/server/wm/DisplayRotation.java
index cf3a688..e6d8b3d 100644
--- a/services/core/java/com/android/server/wm/DisplayRotation.java
+++ b/services/core/java/com/android/server/wm/DisplayRotation.java
@@ -100,6 +100,8 @@
     private final DisplayWindowSettings mDisplayWindowSettings;
     private final Context mContext;
     private final Object mLock;
+    @Nullable
+    private final DisplayRotationImmersiveAppCompatPolicy mCompatPolicyForImmersiveApps;
 
     public final boolean isDefaultDisplay;
     private final boolean mSupportAutoRotation;
@@ -205,7 +207,7 @@
 
     /**
      * A flag to indicate if the display rotation should be fixed to user specified rotation
-     * regardless of all other states (including app requrested orientation). {@code true} the
+     * regardless of all other states (including app requested orientation). {@code true} the
      * display rotation should be fixed to user specified rotation, {@code false} otherwise.
      */
     private int mFixedToUserRotation = IWindowManager.FIXED_TO_USER_ROTATION_DEFAULT;
@@ -232,6 +234,7 @@
         mContext = context;
         mLock = lock;
         isDefaultDisplay = displayContent.isDefaultDisplay;
+        mCompatPolicyForImmersiveApps = initImmersiveAppCompatPolicy(service, displayContent);
 
         mSupportAutoRotation =
                 mContext.getResources().getBoolean(R.bool.config_supportAutoRotation);
@@ -255,6 +258,14 @@
         }
     }
 
+    @VisibleForTesting
+    @Nullable
+    DisplayRotationImmersiveAppCompatPolicy initImmersiveAppCompatPolicy(
+                WindowManagerService service, DisplayContent displayContent) {
+        return DisplayRotationImmersiveAppCompatPolicy.createIfNeeded(
+                service.mLetterboxConfiguration, this, displayContent);
+    }
+
     // Change the default value to the value specified in the sysprop
     // ro.bootanim.set_orientation_<display_id>. Four values are supported: ORIENTATION_0,
     // ORIENTATION_90, ORIENTATION_180 and ORIENTATION_270.
@@ -1305,11 +1316,11 @@
         return mAllowAllRotations;
     }
 
-    private boolean isLandscapeOrSeascape(int rotation) {
+    boolean isLandscapeOrSeascape(@Surface.Rotation final int rotation) {
         return rotation == mLandscapeRotation || rotation == mSeascapeRotation;
     }
 
-    private boolean isAnyPortrait(int rotation) {
+    boolean isAnyPortrait(@Surface.Rotation final int rotation) {
         return rotation == mPortraitRotation || rotation == mUpsideDownRotation;
     }
 
@@ -1348,9 +1359,16 @@
         return mFoldController != null && mFoldController.overrideFrozenRotation();
     }
 
-    private boolean isRotationChoicePossible(int orientation) {
-        // Rotation choice is only shown when the user is in locked mode.
-        if (mUserRotationMode != WindowManagerPolicy.USER_ROTATION_LOCKED) return false;
+    private boolean isRotationChoiceAllowed(@Surface.Rotation final int proposedRotation) {
+        final boolean isRotationLockEnforced = mCompatPolicyForImmersiveApps != null
+                && mCompatPolicyForImmersiveApps.isRotationLockEnforced(proposedRotation);
+
+        // Don't show rotation choice button if
+        if (!isRotationLockEnforced // not enforcing locked rotation
+                // and the screen rotation is not locked by the user.
+                && mUserRotationMode != WindowManagerPolicy.USER_ROTATION_LOCKED) {
+            return false;
+        }
 
         // Don't show rotation choice if we are in tabletop or book modes.
         if (isTabletopAutoRotateOverrideEnabled()) return false;
@@ -1402,7 +1420,7 @@
         }
 
         // Ensure that some rotation choice is possible for the given orientation.
-        switch (orientation) {
+        switch (mCurrentAppOrientation) {
             case ActivityInfo.SCREEN_ORIENTATION_FULL_USER:
             case ActivityInfo.SCREEN_ORIENTATION_USER:
             case ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED:
@@ -1719,11 +1737,11 @@
 
 
         @Override
-        public void onProposedRotationChanged(int rotation) {
+        public void onProposedRotationChanged(@Surface.Rotation int rotation) {
             ProtoLog.v(WM_DEBUG_ORIENTATION, "onProposedRotationChanged, rotation=%d", rotation);
             // Send interaction power boost to improve redraw performance.
             mService.mPowerManagerInternal.setPowerBoost(Boost.INTERACTION, 0);
-            if (isRotationChoicePossible(mCurrentAppOrientation)) {
+            if (isRotationChoiceAllowed(rotation)) {
                 final boolean isValid = isValidRotationChoice(rotation);
                 sendProposedRotationChangeToStatusBarInternal(rotation, isValid);
             } else {
diff --git a/services/core/java/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicy.java b/services/core/java/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicy.java
new file mode 100644
index 0000000..4dad2b2
--- /dev/null
+++ b/services/core/java/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicy.java
@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 2022 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;
+
+import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
+import static android.content.res.Configuration.ORIENTATION_LANDSCAPE;
+import static android.content.res.Configuration.ORIENTATION_PORTRAIT;
+import static android.content.res.Configuration.ORIENTATION_UNDEFINED;
+import static android.view.InsetsState.ITYPE_NAVIGATION_BAR;
+import static android.view.InsetsState.ITYPE_STATUS_BAR;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.res.Configuration.Orientation;
+import android.view.InsetsVisibilities;
+import android.view.Surface;
+
+/**
+ * Policy to decide whether to enforce screen rotation lock for optimisation of the screen rotation
+ * user experience for immersive applications for compatibility when ignoring orientation request.
+ *
+ * <p>This is needed because immersive apps, such as games, are often not optimized for all
+ * orientations and can have a poor UX when rotated (e.g., state loss or entering size-compat mode).
+ * Additionally, some games rely on sensors for the gameplay so users can trigger such rotations
+ * accidentally when auto rotation is on.
+ */
+final class DisplayRotationImmersiveAppCompatPolicy {
+
+    @Nullable
+    static DisplayRotationImmersiveAppCompatPolicy createIfNeeded(
+            @NonNull final LetterboxConfiguration letterboxConfiguration,
+            @NonNull final DisplayRotation displayRotation,
+            @NonNull final DisplayContent displayContent) {
+        if (!letterboxConfiguration
+                .isDisplayRotationImmersiveAppCompatPolicyEnabled(/* checkDeviceConfig */ false)) {
+            return null;
+        }
+
+        return new DisplayRotationImmersiveAppCompatPolicy(
+                letterboxConfiguration, displayRotation, displayContent);
+    }
+
+    private final DisplayRotation mDisplayRotation;
+    private final LetterboxConfiguration mLetterboxConfiguration;
+    private final DisplayContent mDisplayContent;
+
+    private DisplayRotationImmersiveAppCompatPolicy(
+            @NonNull final LetterboxConfiguration letterboxConfiguration,
+            @NonNull final DisplayRotation displayRotation,
+            @NonNull final DisplayContent displayContent) {
+        mDisplayRotation = displayRotation;
+        mLetterboxConfiguration = letterboxConfiguration;
+        mDisplayContent = displayContent;
+    }
+
+    /**
+     * Decides whether it is necessary to lock screen rotation, preventing auto rotation, based on
+     * the top activity configuration and proposed screen rotation.
+     *
+     * <p>This is needed because immersive apps, such as games, are often not optimized for all
+     * orientations and can have a poor UX when rotated. Additionally, some games rely on sensors
+     * for the gameplay so users can trigger such rotations accidentally when auto rotation is on.
+     *
+     * <p>Screen rotation is locked when the following conditions are met:
+     * <ul>
+     *   <li>Top activity requests to hide status and navigation bars
+     *   <li>Top activity is fullscreen and in optimal orientation (without letterboxing)
+     *   <li>Rotation will lead to letterboxing due to fixed orientation.
+     *   <li>{@link DisplayContent#getIgnoreOrientationRequest} is {@code true}
+     *   <li>This policy is enabled on the device, for details see
+     *   {@link LetterboxConfiguration#isDisplayRotationImmersiveAppCompatPolicyEnabled}
+     * </ul>
+     *
+     * @param proposedRotation new proposed {@link Surface.Rotation} for the screen.
+     * @return {@code true}, if there is a need to lock screen rotation, {@code false} otherwise.
+     */
+    boolean isRotationLockEnforced(@Surface.Rotation final int proposedRotation) {
+        if (!mLetterboxConfiguration.isDisplayRotationImmersiveAppCompatPolicyEnabled(
+                /* checkDeviceConfig */ true)) {
+            return false;
+        }
+        synchronized (mDisplayContent.mWmService.mGlobalLock) {
+            return isRotationLockEnforcedLocked(proposedRotation);
+        }
+    }
+
+    private boolean isRotationLockEnforcedLocked(@Surface.Rotation final int proposedRotation) {
+        if (!mDisplayContent.getIgnoreOrientationRequest()) {
+            return false;
+        }
+
+        final ActivityRecord activityRecord = mDisplayContent.topRunningActivity();
+        if (activityRecord == null) {
+            return false;
+        }
+
+        // Don't lock screen rotation if an activity hasn't requested to hide system bars.
+        if (!hasRequestedToHideStatusAndNavBars(activityRecord)) {
+            return false;
+        }
+
+        // Don't lock screen rotation if activity is not in fullscreen. Checking windowing mode
+        // for a task rather than an activity to exclude activity embedding scenario.
+        if (activityRecord.getTask() == null
+                || activityRecord.getTask().getWindowingMode() != WINDOWING_MODE_FULLSCREEN) {
+            return false;
+        }
+
+        // Don't lock screen rotation if activity is letterboxed.
+        if (activityRecord.areBoundsLetterboxed()) {
+            return false;
+        }
+
+        if (activityRecord.getRequestedConfigurationOrientation() == ORIENTATION_UNDEFINED) {
+            return false;
+        }
+
+        // Lock screen rotation only if, after rotation the activity's orientation won't match
+        // the screen orientation, forcing the activity to enter letterbox mode after rotation.
+        return activityRecord.getRequestedConfigurationOrientation()
+                != surfaceRotationToConfigurationOrientation(proposedRotation);
+    }
+
+    /**
+     * Checks whether activity has requested to hide status and navigation bars.
+     */
+    private boolean hasRequestedToHideStatusAndNavBars(@NonNull ActivityRecord activity) {
+        WindowState mainWindow = activity.findMainWindow();
+        if (mainWindow == null) {
+            return false;
+        }
+        InsetsVisibilities insetsVisibilities = mainWindow.getRequestedVisibilities();
+        return !insetsVisibilities.getVisibility(ITYPE_STATUS_BAR)
+                && !insetsVisibilities.getVisibility(ITYPE_NAVIGATION_BAR);
+    }
+
+    @Orientation
+    private int surfaceRotationToConfigurationOrientation(@Surface.Rotation final int rotation) {
+        if (mDisplayRotation.isAnyPortrait(rotation)) {
+            return ORIENTATION_PORTRAIT;
+        } else if (mDisplayRotation.isLandscapeOrSeascape(rotation)) {
+            return ORIENTATION_LANDSCAPE;
+        } else {
+            return ORIENTATION_UNDEFINED;
+        }
+    }
+}
diff --git a/services/core/java/com/android/server/wm/LetterboxConfiguration.java b/services/core/java/com/android/server/wm/LetterboxConfiguration.java
index 5e4f2ae..f916ee4 100644
--- a/services/core/java/com/android/server/wm/LetterboxConfiguration.java
+++ b/services/core/java/com/android/server/wm/LetterboxConfiguration.java
@@ -18,6 +18,7 @@
 
 import static com.android.server.wm.ActivityTaskManagerDebugConfig.TAG_ATM;
 import static com.android.server.wm.ActivityTaskManagerDebugConfig.TAG_WITH_CLASS_NAME;
+import static com.android.server.wm.LetterboxConfigurationDeviceConfig.KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY;
 
 import android.annotation.IntDef;
 import android.annotation.NonNull;
@@ -227,23 +228,35 @@
     // LetterboxUiController#shouldIgnoreRequestedOrientation for details.
     private final boolean mIsPolicyForIgnoringRequestedOrientationEnabled;
 
-    LetterboxConfiguration(Context systemUiContext) {
-        this(systemUiContext, new LetterboxConfigurationPersister(systemUiContext,
-                () -> readLetterboxHorizontalReachabilityPositionFromConfig(systemUiContext,
-                        /* forBookMode */ false),
-                () -> readLetterboxVerticalReachabilityPositionFromConfig(systemUiContext,
-                        /* forTabletopMode */ false),
-                () -> readLetterboxHorizontalReachabilityPositionFromConfig(systemUiContext,
-                        /* forBookMode */ true),
-                () -> readLetterboxVerticalReachabilityPositionFromConfig(systemUiContext,
-                        /* forTabletopMode */ true)
-        ));
+    // Whether enabling rotation compat policy for immersive apps that prevents auto rotation
+    // into non-optimal screen orientation while in fullscreen. This is needed because immersive
+    // apps, such as games, are often not optimized for all orientations and can have a poor UX
+    // when rotated. Additionally, some games rely on sensors for the gameplay so users can trigger
+    // such rotations accidentally when auto rotation is on.
+    private final boolean mIsDisplayRotationImmersiveAppCompatPolicyEnabled;
+
+    // Flags dynamically updated with {@link android.provider.DeviceConfig}.
+    @NonNull private final LetterboxConfigurationDeviceConfig mDeviceConfig;
+
+    LetterboxConfiguration(@NonNull final Context systemUiContext) {
+        this(systemUiContext,
+                new LetterboxConfigurationPersister(systemUiContext,
+                        () -> readLetterboxHorizontalReachabilityPositionFromConfig(
+                                systemUiContext, /* forBookMode */ false),
+                        () -> readLetterboxVerticalReachabilityPositionFromConfig(
+                                systemUiContext, /* forTabletopMode */ false),
+                        () -> readLetterboxHorizontalReachabilityPositionFromConfig(
+                                systemUiContext, /* forBookMode */ true),
+                        () -> readLetterboxVerticalReachabilityPositionFromConfig(
+                                systemUiContext, /* forTabletopMode */ true)));
     }
 
     @VisibleForTesting
-    LetterboxConfiguration(Context systemUiContext,
-            LetterboxConfigurationPersister letterboxConfigurationPersister) {
+    LetterboxConfiguration(@NonNull final Context systemUiContext,
+            @NonNull final LetterboxConfigurationPersister letterboxConfigurationPersister) {
         mContext = systemUiContext;
+        mDeviceConfig = new LetterboxConfigurationDeviceConfig(systemUiContext.getMainExecutor());
+
         mFixedOrientationLetterboxAspectRatio = mContext.getResources().getFloat(
                 R.dimen.config_fixedOrientationLetterboxAspectRatio);
         mLetterboxActivityCornersRadius = mContext.getResources().getInteger(
@@ -284,6 +297,12 @@
         mIsPolicyForIgnoringRequestedOrientationEnabled = mContext.getResources().getBoolean(
                 R.bool.config_letterboxIsPolicyForIgnoringRequestedOrientationEnabled);
 
+        mIsDisplayRotationImmersiveAppCompatPolicyEnabled = mContext.getResources().getBoolean(
+                R.bool.config_letterboxIsDisplayRotationImmersiveAppCompatPolicyEnabled);
+        mDeviceConfig.updateFlagActiveStatus(
+                /* isActive */ mIsDisplayRotationImmersiveAppCompatPolicyEnabled,
+                /* key */ KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY);
+
         mLetterboxConfigurationPersister = letterboxConfigurationPersister;
         mLetterboxConfigurationPersister.start();
     }
@@ -1105,4 +1124,20 @@
         mIsCameraCompatRefreshCycleThroughStopEnabled = true;
     }
 
+    /**
+     * Checks whether rotation compat policy for immersive apps that prevents auto rotation
+     * into non-optimal screen orientation while in fullscreen is enabled.
+     *
+     * <p>This is needed because immersive apps, such as games, are often not optimized for all
+     * orientations and can have a poor UX when rotated. Additionally, some games rely on sensors
+     * for the gameplay so users can trigger such rotations accidentally when auto rotation is on.
+     *
+     * @param checkDeviceConfig whether should check both static config and a dynamic property
+     *        from {@link DeviceConfig} or only static value.
+     */
+    boolean isDisplayRotationImmersiveAppCompatPolicyEnabled(final boolean checkDeviceConfig) {
+        return mIsDisplayRotationImmersiveAppCompatPolicyEnabled && (!checkDeviceConfig
+                || mDeviceConfig.getFlag(KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY));
+    }
+
 }
diff --git a/services/core/java/com/android/server/wm/LetterboxConfigurationDeviceConfig.java b/services/core/java/com/android/server/wm/LetterboxConfigurationDeviceConfig.java
new file mode 100644
index 0000000..cf123a1
--- /dev/null
+++ b/services/core/java/com/android/server/wm/LetterboxConfigurationDeviceConfig.java
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2022 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;
+
+import android.annotation.NonNull;
+import android.provider.DeviceConfig;
+import android.util.ArraySet;
+
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.util.Map;
+import java.util.concurrent.Executor;
+
+/**
+ * Utility class that caches {@link DeviceConfig} flags for app compat features and listens
+ * to updates by implementing {@link DeviceConfig.OnPropertiesChangedListener}.
+ */
+final class LetterboxConfigurationDeviceConfig
+        implements DeviceConfig.OnPropertiesChangedListener {
+
+    static final String KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY =
+            "enable_display_rotation_immersive_app_compat_policy";
+    private static final boolean DEFAULT_VALUE_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY =
+            true;
+
+    @VisibleForTesting
+    static final Map<String, Boolean> sKeyToDefaultValueMap = Map.of(
+            KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY,
+            DEFAULT_VALUE_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY
+    );
+
+    // Whether enabling rotation compat policy for immersive apps that prevents auto rotation
+    // into non-optimal screen orientation while in fullscreen. This is needed because immersive
+    // apps, such as games, are often not optimized for all orientations and can have a poor UX
+    // when rotated. Additionally, some games rely on sensors for the gameplay so users can trigger
+    // such rotations accidentally when auto rotation is on.
+    private boolean mIsDisplayRotationImmersiveAppCompatPolicyEnabled =
+            DEFAULT_VALUE_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY;
+
+    // Set of active device configs that need to be updated in
+    // DeviceConfig.OnPropertiesChangedListener#onPropertiesChanged.
+    private final ArraySet<String> mActiveDeviceConfigsSet = new ArraySet<>();
+
+    LetterboxConfigurationDeviceConfig(@NonNull final Executor executor) {
+        DeviceConfig.addOnPropertiesChangedListener(DeviceConfig.NAMESPACE_WINDOW_MANAGER,
+                executor, /* onPropertiesChangedListener */ this);
+    }
+
+    @Override
+    public void onPropertiesChanged(@NonNull final DeviceConfig.Properties properties) {
+        for (int i = mActiveDeviceConfigsSet.size() - 1; i >= 0; i--) {
+            String key = mActiveDeviceConfigsSet.valueAt(i);
+            // Reads the new configuration, if the device config properties contain the key.
+            if (properties.getKeyset().contains(key)) {
+                readAndSaveValueFromDeviceConfig(key);
+            }
+        }
+    }
+
+    /**
+     * Adds {@code key} to a set of flags that can be updated from the server if
+     * {@code isActive} is {@code true} and read it's current value from {@link DeviceConfig}.
+     */
+    void updateFlagActiveStatus(boolean isActive, String key) {
+        if (!isActive) {
+            return;
+        }
+        mActiveDeviceConfigsSet.add(key);
+        readAndSaveValueFromDeviceConfig(key);
+    }
+
+    /**
+     * Returns values of the {@code key} flag.
+     *
+     * @throws AssertionError {@code key} isn't recognised.
+     */
+    boolean getFlag(String key) {
+        switch (key) {
+            case KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY:
+                return mIsDisplayRotationImmersiveAppCompatPolicyEnabled;
+            default:
+                throw new AssertionError("Unexpected flag name: " + key);
+        }
+    }
+
+    private void readAndSaveValueFromDeviceConfig(String key) {
+        Boolean defaultValue = sKeyToDefaultValueMap.get(key);
+        if (defaultValue == null) {
+            throw new AssertionError("Haven't found default value for flag: " + key);
+        }
+        switch (key) {
+            case KEY_ENABLE_DISPLAY_ROTATION_IMMERSIVE_APP_COMPAT_POLICY:
+                mIsDisplayRotationImmersiveAppCompatPolicyEnabled =
+                        getDeviceConfig(key, defaultValue);
+                break;
+            default:
+                throw new AssertionError("Unexpected flag name: " + key);
+        }
+    }
+
+    private boolean getDeviceConfig(String key, boolean defaultValue) {
+        return DeviceConfig.getBoolean(DeviceConfig.NAMESPACE_WINDOW_MANAGER,
+                key, defaultValue);
+    }
+}
diff --git a/services/tests/wmtests/Android.bp b/services/tests/wmtests/Android.bp
index 079d765..2ce7cea 100644
--- a/services/tests/wmtests/Android.bp
+++ b/services/tests/wmtests/Android.bp
@@ -68,6 +68,10 @@
         "android.test.runner",
     ],
 
+    defaults: [
+        "modules-utils-testable-device-config-defaults",
+    ],
+
     // These are not normally accessible from apps so they must be explicitly included.
     jni_libs: [
         "libdexmakerjvmtiagent",
diff --git a/services/tests/wmtests/src/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicyTests.java b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicyTests.java
new file mode 100644
index 0000000..def4b88
--- /dev/null
+++ b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationImmersiveAppCompatPolicyTests.java
@@ -0,0 +1,225 @@
+/*
+ * Copyright (C) 2022 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;
+
+import static android.app.WindowConfiguration.WINDOWING_MODE_FREEFORM;
+import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
+import static android.app.WindowConfiguration.WINDOWING_MODE_MULTI_WINDOW;
+import static android.app.WindowConfiguration.WINDOWING_MODE_PINNED;
+import static android.content.res.Configuration.ORIENTATION_LANDSCAPE;
+import static android.content.res.Configuration.ORIENTATION_PORTRAIT;
+import static android.content.res.Configuration.ORIENTATION_UNDEFINED;
+import static android.view.InsetsState.ITYPE_NAVIGATION_BAR;
+import static android.view.InsetsState.ITYPE_STATUS_BAR;
+
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.eq;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.mock;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.spy;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.when;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.anyBoolean;
+
+import android.platform.test.annotations.Presubmit;
+import android.view.InsetsVisibilities;
+import android.view.Surface;
+
+import androidx.test.filters.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+/**
+ * Test class for {@link DisplayRotationImmersiveAppCompatPolicy}.
+ *
+ * Build/Install/Run:
+ *  atest WmTests:DisplayRotationImmersiveAppCompatPolicyTests
+ */
+@SmallTest
+@Presubmit
+@RunWith(WindowTestRunner.class)
+public class DisplayRotationImmersiveAppCompatPolicyTests extends WindowTestsBase {
+
+    private DisplayRotationImmersiveAppCompatPolicy mPolicy;
+
+    private LetterboxConfiguration mMockLetterboxConfiguration;
+    private ActivityRecord mMockActivityRecord;
+    private Task mMockTask;
+    private InsetsVisibilities mMockInsetsVisibilities;
+
+    @Before
+    public void setUp() throws Exception {
+        mMockActivityRecord = mock(ActivityRecord.class);
+        mMockTask = mock(Task.class);
+        when(mMockTask.getWindowingMode()).thenReturn(WINDOWING_MODE_FULLSCREEN);
+        when(mMockActivityRecord.getTask()).thenReturn(mMockTask);
+        when(mMockActivityRecord.areBoundsLetterboxed()).thenReturn(false);
+        when(mMockActivityRecord.getRequestedConfigurationOrientation()).thenReturn(
+                ORIENTATION_LANDSCAPE);
+        WindowState mockWindowState = mock(WindowState.class);
+        mMockInsetsVisibilities = mock(InsetsVisibilities.class);
+        when(mMockInsetsVisibilities.getVisibility(eq(ITYPE_STATUS_BAR))).thenReturn(false);
+        when(mMockInsetsVisibilities.getVisibility(eq(ITYPE_NAVIGATION_BAR))).thenReturn(false);
+        when(mockWindowState.getRequestedVisibilities()).thenReturn(mMockInsetsVisibilities);
+        when(mMockActivityRecord.findMainWindow()).thenReturn(mockWindowState);
+
+        spy(mDisplayContent);
+        doReturn(mMockActivityRecord).when(mDisplayContent).topRunningActivity();
+        when(mDisplayContent.getIgnoreOrientationRequest()).thenReturn(true);
+
+        mMockLetterboxConfiguration = mock(LetterboxConfiguration.class);
+        when(mMockLetterboxConfiguration.isDisplayRotationImmersiveAppCompatPolicyEnabled(
+                /* checkDeviceConfig */ anyBoolean())).thenReturn(true);
+
+        mPolicy = DisplayRotationImmersiveAppCompatPolicy.createIfNeeded(
+                mMockLetterboxConfiguration, createDisplayRotationMock(),
+                mDisplayContent);
+    }
+
+    private DisplayRotation createDisplayRotationMock() {
+        DisplayRotation mockDisplayRotation = mock(DisplayRotation.class);
+
+        when(mockDisplayRotation.isAnyPortrait(Surface.ROTATION_0)).thenReturn(true);
+        when(mockDisplayRotation.isAnyPortrait(Surface.ROTATION_90)).thenReturn(false);
+        when(mockDisplayRotation.isAnyPortrait(Surface.ROTATION_180)).thenReturn(true);
+        when(mockDisplayRotation.isAnyPortrait(Surface.ROTATION_270)).thenReturn(false);
+        when(mockDisplayRotation.isLandscapeOrSeascape(Surface.ROTATION_0)).thenReturn(false);
+        when(mockDisplayRotation.isLandscapeOrSeascape(Surface.ROTATION_90)).thenReturn(true);
+        when(mockDisplayRotation.isLandscapeOrSeascape(Surface.ROTATION_180)).thenReturn(false);
+        when(mockDisplayRotation.isLandscapeOrSeascape(Surface.ROTATION_270)).thenReturn(true);
+
+        return mockDisplayRotation;
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_landscapeActivity_lockedWhenRotatingToPortrait() {
+        // Base case: App is optimal in Landscape.
+
+        // ROTATION_* is the target display orientation counted from the natural display
+        // orientation. Outside of test environment, ROTATION_0 means that proposed display
+        // rotation is the natural device orientation.
+        // DisplayRotationImmersiveAppCompatPolicy assesses whether the proposed target
+        // orientation ROTATION_* is optimal for the top fullscreen activity or not.
+        // For instance, ROTATION_0 means portrait screen orientation (see
+        // createDisplayRotationMock) which isn't optimal for a landscape-only activity so
+        // we should show a rotation suggestion button instead of rotating directly.
+
+        // Rotation to portrait
+        assertTrue(mPolicy.isRotationLockEnforced(Surface.ROTATION_0));
+        // Rotation to landscape
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_90));
+        // Rotation to portrait
+        assertTrue(mPolicy.isRotationLockEnforced(Surface.ROTATION_180));
+        // Rotation to landscape
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_270));
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_portraitActivity_lockedWhenRotatingToLandscape() {
+        when(mMockActivityRecord.getRequestedConfigurationOrientation()).thenReturn(
+                ORIENTATION_PORTRAIT);
+
+        // Rotation to portrait
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_0));
+        // Rotation to landscape
+        assertTrue(mPolicy.isRotationLockEnforced(Surface.ROTATION_90));
+        // Rotation to portrait
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_180));
+        // Rotation to landscape
+        assertTrue(mPolicy.isRotationLockEnforced(Surface.ROTATION_270));
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_responsiveActivity_lockNotEnforced() {
+        // Do not fix screen orientation
+        when(mMockActivityRecord.getRequestedConfigurationOrientation()).thenReturn(
+                ORIENTATION_UNDEFINED);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_statusBarVisible_lockNotEnforced() {
+        // Some system bars are visible
+        when(mMockInsetsVisibilities.getVisibility(eq(ITYPE_STATUS_BAR))).thenReturn(true);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_navBarVisible_lockNotEnforced() {
+        // Some system bars are visible
+        when(mMockInsetsVisibilities.getVisibility(eq(ITYPE_NAVIGATION_BAR))).thenReturn(true);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_activityIsLetterboxed_lockNotEnforced() {
+        // Activity is letterboxed
+        when(mMockActivityRecord.areBoundsLetterboxed()).thenReturn(true);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_notFullscreen_lockNotEnforced() {
+        when(mMockTask.getWindowingMode()).thenReturn(WINDOWING_MODE_MULTI_WINDOW);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+
+        when(mMockTask.getWindowingMode()).thenReturn(WINDOWING_MODE_PINNED);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+
+        when(mMockTask.getWindowingMode()).thenReturn(WINDOWING_MODE_FREEFORM);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testIsRotationLockEnforced_ignoreOrientationRequestDisabled_lockNotEnforced() {
+        when(mDisplayContent.getIgnoreOrientationRequest()).thenReturn(false);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testRotationChoiceEnforcedOnly_nullTopRunningActivity_lockNotEnforced() {
+        when(mDisplayContent.topRunningActivity()).thenReturn(null);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    @Test
+    public void testRotationChoiceEnforcedOnly_featureFlagDisabled_lockNotEnforced() {
+        when(mMockLetterboxConfiguration.isDisplayRotationImmersiveAppCompatPolicyEnabled(
+                /* checkDeviceConfig */ true)).thenReturn(false);
+
+        assertIsRotationLockEnforcedReturnsFalseForAllRotations();
+    }
+
+    private void assertIsRotationLockEnforcedReturnsFalseForAllRotations() {
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_0));
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_90));
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_180));
+        assertFalse(mPolicy.isRotationLockEnforced(Surface.ROTATION_270));
+    }
+}
diff --git a/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
index 491f876d..4ce43e1 100644
--- a/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
@@ -1096,8 +1096,16 @@
             mMockDisplayAddress = mock(DisplayAddress.class);
 
             mMockDisplayWindowSettings = mock(DisplayWindowSettings.class);
+
             mTarget = new DisplayRotation(sMockWm, mMockDisplayContent, mMockDisplayAddress,
-                    mMockDisplayPolicy, mMockDisplayWindowSettings, mMockContext, new Object());
+                    mMockDisplayPolicy, mMockDisplayWindowSettings, mMockContext, new Object()) {
+                @Override
+                DisplayRotationImmersiveAppCompatPolicy initImmersiveAppCompatPolicy(
+                        WindowManagerService service, DisplayContent displayContent) {
+                    return null;
+                }
+            };
+
             reset(sMockWm);
 
             captureObservers();
diff --git a/services/tests/wmtests/src/com/android/server/wm/LetterboxConfigurationDeviceConfigTests.java b/services/tests/wmtests/src/com/android/server/wm/LetterboxConfigurationDeviceConfigTests.java
new file mode 100644
index 0000000..2b7a06b
--- /dev/null
+++ b/services/tests/wmtests/src/com/android/server/wm/LetterboxConfigurationDeviceConfigTests.java
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2022 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;
+
+import static com.android.server.wm.LetterboxConfigurationDeviceConfig.sKeyToDefaultValueMap;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import android.platform.test.annotations.Presubmit;
+import android.provider.DeviceConfig;
+
+import androidx.test.filters.SmallTest;
+
+import com.android.modules.utils.testing.TestableDeviceConfig;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Map;
+
+/**
+ * Test class for {@link LetterboxConfigurationDeviceConfig}.
+ *
+ * atest WmTests:LetterboxConfigurationDeviceConfigTests
+ */
+@SmallTest
+@Presubmit
+public class LetterboxConfigurationDeviceConfigTests {
+
+    private LetterboxConfigurationDeviceConfig mDeviceConfig;
+
+    @Rule
+    public final TestableDeviceConfig.TestableDeviceConfigRule
+            mDeviceConfigRule = new TestableDeviceConfig.TestableDeviceConfigRule();
+
+    @Before
+    public void setUp() {
+        mDeviceConfig = new LetterboxConfigurationDeviceConfig(/* executor */ Runnable::run);
+    }
+
+    @Test
+    public void testGetFlag_flagIsActive_flagChanges() throws Throwable {
+        for (Map.Entry<String, Boolean> entry : sKeyToDefaultValueMap.entrySet()) {
+            testGetFlagForKey_flagIsActive_flagChanges(entry.getKey(), entry.getValue());
+        }
+    }
+
+    private void testGetFlagForKey_flagIsActive_flagChanges(final String key, boolean defaultValue)
+            throws InterruptedException {
+        mDeviceConfig.updateFlagActiveStatus(/* isActive */ true, key);
+
+        assertEquals("Unexpected default value for " + key,
+                mDeviceConfig.getFlag(key), defaultValue);
+
+        DeviceConfig.setProperty(DeviceConfig.NAMESPACE_WINDOW_MANAGER, key,
+                /* value */ Boolean.TRUE.toString(), /* makeDefault */ false);
+
+        assertTrue("Flag " + key + "is not true after change", mDeviceConfig.getFlag(key));
+
+        DeviceConfig.setProperty(DeviceConfig.NAMESPACE_WINDOW_MANAGER, key,
+                /* value */ Boolean.FALSE.toString(), /* makeDefault */ false);
+
+        assertFalse("Flag " + key + "is not false after change", mDeviceConfig.getFlag(key));
+    }
+
+    @Test
+    public void testGetFlag_flagIsNotActive_alwaysReturnDefaultValue() throws Throwable {
+        for (Map.Entry<String, Boolean> entry : sKeyToDefaultValueMap.entrySet()) {
+            testGetFlagForKey_flagIsNotActive_alwaysReturnDefaultValue(
+                    entry.getKey(), entry.getValue());
+        }
+    }
+
+    private void testGetFlagForKey_flagIsNotActive_alwaysReturnDefaultValue(final String key,
+            boolean defaultValue) throws InterruptedException {
+        assertEquals("Unexpected default value for " + key,
+                mDeviceConfig.getFlag(key), defaultValue);
+
+        DeviceConfig.setProperty(DeviceConfig.NAMESPACE_WINDOW_MANAGER, key,
+                /* value */ Boolean.TRUE.toString(), /* makeDefault */ false);
+
+        assertEquals("Flag " + key + "is not set to default after change",
+                mDeviceConfig.getFlag(key), defaultValue);
+
+        DeviceConfig.setProperty(DeviceConfig.NAMESPACE_WINDOW_MANAGER, key,
+                /* value */ Boolean.FALSE.toString(), /* makeDefault */ false);
+
+        assertEquals("Flag " + key + "is not set to default after change",
+                mDeviceConfig.getFlag(key), defaultValue);
+    }
+
+}