6410637: Make decision on deprecated methods in DefaultFileManager and BaseFileObject.
6747645: ZipFileObject.getName is incorrectly deprecated
6885123: JavaFileObject getName issues
Reviewed-by: mcimadamore
6517779: javax.lang.model.util.Elements.getConstantExpression() doesn't throw any exception
6517907: javax.lang.model.util.Elements.getConstantExpression() with negative byte value fails
Summary: Fix various problems with Elements.getConstantExpression()
Reviewed-by: jjg