RFR: 8023524: Mechanism to dump generated lambda classes / log lambda code generation

[Henry Jen]

Hi,

Please review updated webrev at
http://cr.openjdk.java.net/~henryjen/ccc/8023524/6/webrev

In this update,

- Check the specified directory once, disable dumping if it is invalid.
This address the comment of unnecessary complexity, as this is a debug
feature and most likely developer would like to restart.
- minimum doPrivilege permission
- Install security manager in test to verify doPrivilege

Cheers,
Henry