locked security.level in system properties is overridden when running 7u21 for the first time.

Steps to reproduce:
1. Create system level deployment.properties file.
Create the deployment.properties under c:\Windows\Sun\Java\Deployment
Set the property in it:
deployment.security.level=MEDIUM
deployment.security.level.locked=true
2. Remove the user level property file from {deployment_home}\deployment.properties.
3. Open JCP
4. If we can see Security Level is High, bug is reproducible.Expecting Medium.


Note:
Opening JCP will generate a new user level file, which contains deployment.security.level=HIGH. So it will cover the system level properties. If we only remove the deployment.security.level=HIGH, system level properties will work again.
But consider the product environment, system level properties should still work when user properties file is absent.