hg: jdk/sandbox: 8211045: [Testbug] Fix for 8144279 didn't define a test case!

[chris.hegarty at oracle.com]

Changeset: 6c17cf410d7c
Author:    dholmes
Date:      2018-09-24 12:18 -0400
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/6c17cf410d7c

8211045: [Testbug] Fix for 8144279 didn't define a test case!
Summary: add missing file from original commit
Reviewed-by: shade, sgehwolf

+ test/hotspot/jtreg/runtime/jsig/Testjsig.java