Enabling wifi on new demo session

A customer may switch off wifi in a retail environment, which will lead
to no internet connectivity in the following sessions, which is not
desirable. Fixing it by enabling wifi at the beginning of every new demo
session.

Bug: 31689469
Change-Id: Ie7eb17bfe8fbee185d5bfe6ac7a590ca5dabdc29

services/retaildemo/java/com/android/server/retaildemo/RetailDemoModeService.java

@@ -44,6 +44,7 @@ import android.hardware.camera2.CameraManager;
 import android.media.AudioManager;
 import android.media.AudioSystem;
 import android.net.Uri;
+import android.net.wifi.WifiManager;
 import android.os.Environment;
 import android.os.FileUtils;
 import android.os.Handler;
@@ -117,6 +118,7 @@ public class RetailDemoModeService extends SystemService {
     private ServiceThread mHandlerThread;
     private PendingIntent mResetDemoPendingIntent;
     private CameraManager mCameraManager;
+    private WifiManager mWifiManager;
     private String[] mCameraIdsWithFlash;
     private Configuration mSystemUserConfiguration;
     private PreloadAppsInstaller mPreloadAppsInstaller;
@@ -491,6 +493,7 @@ public class RetailDemoModeService extends SystemService {
                                 PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP,
                                 TAG);
                 mNm = NotificationManager.from(getContext());
+                mWifiManager = (WifiManager) getContext().getSystemService(Context.WIFI_SERVICE);
                 mCameraManager = (CameraManager) getContext()
                         .getSystemService(Context.CAMERA_SERVICE);
                 mCameraIdsWithFlash = getCameraIdsWithFlash();
@@ -528,6 +531,9 @@ public class RetailDemoModeService extends SystemService {
         mAmi.updatePersistentConfigurationForUser(getSystemUsersConfiguration(), userId);
         turnOffAllFlashLights();
         muteVolumeStreams();
+        if (!mWifiManager.isWifiEnabled()) {
+            mWifiManager.setWifiEnabled(true);
+        }
         // Disable lock screen for demo users.
         LockPatternUtils lockPatternUtils = new LockPatternUtils(getContext());
         lockPatternUtils.setLockScreenDisabled(true, userId);