Restore the up time preference.

- up time preference is removed when we updated to the new version of
about phone settings. Add it back to the preference xml, and restore the
controller for it.

Change-Id: I245316e84d04f9d6f033377c944b615dd6e138a5
Fixes: 111828610
Test: manual

res/xml/my_device_info.xml

@@ -133,6 +133,14 @@
         android:summary="@string/summary_placeholder"
         android:selectable="false"/>
 
+    <!-- Device up time -->
+    <Preference
+        android:key="up_time"
+        android:order="37"
+        android:title="@string/status_up_time"
+        android:summary="@string/summary_placeholder"
+        android:selectable="false" />
+
     <!-- Safety & regulatory manual -->
     <Preference
         android:key="safety_info"

src/com/android/settings/deviceinfo/UptimePreferenceController.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2018 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.settings.deviceinfo;
+
+import android.content.Context;
+
+import com.android.settings.core.PreferenceControllerMixin;
+import com.android.settingslib.core.lifecycle.Lifecycle;
+import com.android.settingslib.deviceinfo.AbstractUptimePreferenceController;
+
+/**
+ * Concrete subclass of uptime preference controller
+ */
+public class UptimePreferenceController extends AbstractUptimePreferenceController
+        implements PreferenceControllerMixin {
+    public UptimePreferenceController(Context context, Lifecycle lifecycle) {
+        super(context, lifecycle);
+    }
+
+    // This space intentionally left blank
+}

src/com/android/settings/deviceinfo/aboutphone/MyDeviceInfoFragment.java

@@ -46,6 +46,7 @@ import com.android.settings.deviceinfo.ManualPreferenceController;
 import com.android.settings.deviceinfo.PhoneNumberPreferenceController;
 import com.android.settings.deviceinfo.RegulatoryInfoPreferenceController;
 import com.android.settings.deviceinfo.SafetyInfoPreferenceController;
+import com.android.settings.deviceinfo.UptimePreferenceController;
 import com.android.settings.deviceinfo.WifiMacAddressPreferenceController;
 import com.android.settings.deviceinfo.firmwareversion.FirmwareVersionPreferenceController;
 import com.android.settings.deviceinfo.imei.ImeiInfoPreferenceController;
@@ -134,6 +135,7 @@ public class MyDeviceInfoFragment extends DashboardFragment
         controllers.add(new FccEquipmentIdPreferenceController(context));
         controllers.add(
                 new BuildNumberPreferenceController(context, activity, fragment, lifecycle));
+        controllers.add(new UptimePreferenceController(context, lifecycle));
         return controllers;
     }