hg: amber/amber: adding test to check that javac is not doing DCE for subclasses of j.l.s.Constable

[vicente.romero at oracle.com]

Changeset: bfe9f5ccf4a0
Author:    vromero
Date:      2018-03-07 11:46 -0500
URL:       http://hg.openjdk.java.net/amber/amber/rev/bfe9f5ccf4a0

adding test to check that javac is not doing DCE for subclasses of j.l.s.Constable

+ test/langtools/tools/javac/specialConstantFolding/dead_code_elimination/DontDoDCEOfConstableTest.java