hg: jdk/sandbox: Converting the test to a combo-framework test.

[jan.lahoda at oracle.com]

Changeset: d885633d9de4
Author:    jlahoda
Date:      2019-09-24 15:40 +0200
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/d885633d9de4

Converting the test to a combo-framework test.

! src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTaskPool.java
! src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java
! src/jdk.compiler/share/classes/com/sun/tools/javac/file/BaseFileManager.java
! src/jdk.compiler/share/classes/com/sun/tools/javac/util/MandatoryWarningHandler.java
! test/langtools/tools/javac/lib/combo/ComboInstance.java
! test/langtools/tools/javac/preview/PreviewErrors.java