hg: amber/amber: adding regression tests, plus bug fixing

[vicente.romero at oracle.com]

Changeset: fff84ca16810
Author:    vromero
Date:      2019-02-13 16:07 -0500
URL:       http://hg.openjdk.java.net/amber/amber/rev/fff84ca16810

adding regression tests, plus bug fixing

! src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
! test/langtools/tools/javac/sealed/SealedDiffConfigurationsTest.java
! test/langtools/tools/javac/sealed/SealedTest01.out
! test/langtools/tools/javac/sealed/separate/TestSeparate_Neg.out