hg: amber/amber: allow records with no parameters

[vicente.romero at oracle.com]

Changeset: 89969d71c998
Author:    vromero
Date:      2018-10-29 16:25 -0400
URL:       http://hg.openjdk.java.net/amber/amber/rev/89969d71c998

allow records with no parameters

! src/jdk.compiler/share/classes/com/sun/tools/javac/parser/JavacParser.java
! src/jdk.compiler/share/classes/com/sun/tools/javac/resources/compiler.properties
- test/langtools/tools/javac/datum/DatumShouldDeclareAtLeastOneFieldTest.java
- test/langtools/tools/javac/datum/DatumShouldDeclareAtLeastOneFieldTest.out