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

[Henry Jen]

Hi,

Please review update of the webrev at
http://cr.openjdk.java.net/~henryjen/ccc/8023524/4/webrev

This update address comments from Remi and Peter,

- Remove the unnecessary static field, also take out not needed
singleton behavior of ProxyClassesDumper
- Ensure InvalidPathException won't stop InnerClassLambdaMetaFactory
- Change test code to create readonly directory that didn't work
properly on Windows.

Cheers,
Henry