Lockdown settings in retail demo mode

When running in demo mode, additionally disable
the following settings screens:
- Date & Time
- More (network settings)

Bug: 27280140

Change-Id: I3132d0c46b24e1e9ca3842af058073eee3df0c90
diff --git a/src/com/android/settings/WirelessSettings.java b/src/com/android/settings/WirelessSettings.java
index 722a861..7e3b8d8 100644
--- a/src/com/android/settings/WirelessSettings.java
+++ b/src/com/android/settings/WirelessSettings.java
@@ -57,6 +57,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 public class WirelessSettings extends SettingsPreferenceFragment implements Indexable {
@@ -410,6 +411,10 @@
             @Override
             public List<SearchIndexableResource> getXmlResourcesToIndex(
                     Context context, boolean enabled) {
+                // Remove wireless settings from search in demo mode
+                if (UserManager.isDeviceInDemoMode(context)) {
+                    return Collections.emptyList();
+                }
                 SearchIndexableResource sir = new SearchIndexableResource(context);
                 sir.xmlResId = R.xml.wireless_settings;
                 return Arrays.asList(sir);