JDK-8170832 adds support for a new properly specified env variable for the launcher: JAVA_OPTIONS. The general intent is that such env variables should follow a consistent pattern.

JDK-8156962 added _JAVA_OPTIONS. We should updtae that code to follow the new guidelines. Specifically,
1. it should be renamed to JAVAC_OPTIONS,
2. it should follow the same quoting rules
3. it should generate a similar warning message to javac's version of stderr, i.e. Log.getWriter(WriterKind.STDERR)