Add support for A/B (Seamless) System Updates

Loosely based on:
0465cb691d

src/org/lineageos/updater/UpdaterReceiver.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2017 The LineageOS 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 org.lineageos.updater;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.os.PowerManager;
+
+public class UpdaterReceiver extends BroadcastReceiver {
+
+    public static final String ACTION_INSTALL_REBOOT =
+            "org.lineageos.updater.action.INSTALL_REBOOT";
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (ACTION_INSTALL_REBOOT.equals(intent.getAction())) {
+            PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
+            pm.reboot(null);
+        }
+    }
+}