do not allow monkey to flip OEM unlock flag

Bug: 11435021
Change-Id: I3a6865bc6c9fde245d8f4af3230716eac4a3f1b1
diff --git a/services/core/java/com/android/server/PersistentDataBlockService.java b/services/core/java/com/android/server/PersistentDataBlockService.java
index 2896f60..6f378fd 100644
--- a/services/core/java/com/android/server/PersistentDataBlockService.java
+++ b/services/core/java/com/android/server/PersistentDataBlockService.java
@@ -17,6 +17,7 @@
 package com.android.server;
 
 import android.Manifest;
+import android.app.ActivityManager;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.os.Binder;
@@ -26,7 +27,9 @@
 import android.os.UserHandle;
 import android.service.persistentdata.IPersistentDataBlockService;
 import android.util.Slog;
+
 import com.android.internal.R;
+
 import libcore.io.IoUtils;
 
 import java.io.DataInputStream;
@@ -241,6 +244,10 @@
 
         @Override
         public void setOemUnlockEnabled(boolean enabled) {
+            // do not allow monkey to flip the flag
+            if (ActivityManager.isUserAMonkey()) {
+                return;
+            }
             enforceOemUnlockPermission();
             FileOutputStream outputStream;
             try {