Add fold_grace_period_enabled flag

Bug: 308417021
Flag: ACONFIG com.android.internal.foldables.flags.fold_grace_period_enabled DEVELOPMENT
Test: builds

Change-Id: Id8db4e7aef744c945771725363a94d479b858661

core/java/com/android/internal/foldables/FoldGracePeriodProvider.java

+/*
+ * 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 com.android.internal.foldables;
+
+import android.os.Build;
+import android.sysprop.FoldLockBehaviorProperties;
+import android.util.Slog;
+
+import com.android.internal.foldables.flags.Flags;
+
+import java.util.function.Supplier;
+
+/**
+ * Wrapper class to access {@link FoldLockBehaviorProperties}.
+ */
+public class FoldGracePeriodProvider {
+
+    private static final String TAG = "FoldGracePeriodProvider";
+    private final Supplier<Boolean> mFoldGracePeriodEnabled = Flags::foldGracePeriodEnabled;
+
+    /**
+     * Whether the fold grace period feature is enabled.
+     */
+    public boolean isEnabled() {
+        if ((Build.IS_ENG || Build.IS_USERDEBUG)
+                && FoldLockBehaviorProperties.fold_grace_period_enabled().orElse(false)) {
+            return true;
+        }
+        try {
+            return mFoldGracePeriodEnabled.get();
+        } catch (Throwable ex) {
+            Slog.i(TAG,
+                    "Flags not ready yet. Return false for "
+                            + Flags.FLAG_FOLD_GRACE_PERIOD_ENABLED,
+                    ex);
+            return false;
+        }
+    }
+}

core/java/com/android/internal/foldables/fold_lock_setting_flags.aconfig

@@ -7,3 +7,11 @@ flag {
     bug: "274447767"
     is_fixed_read_only: true
 }
+
+flag {
+    name: "fold_grace_period_enabled"
+    namespace: "display_manager"
+    description: "Feature flag for Folding Grace Period"
+    bug: "308417021"
+    is_fixed_read_only: true
+}

core/sysprop/FoldLockBehaviorProperties.sysprop

@@ -22,3 +22,11 @@ prop {
     scope: Internal
     access: Readonly
 }
+
+prop {
+    api_name: "fold_grace_period_enabled"
+    type: Boolean
+    prop_name: "persist.fold_grace_period_enabled"
+    scope: Internal
+    access: Readonly
+}