hg: jigsaw/jake/nashorn: Bump jtreg requiredVersion to 4.2

[mandy . chung]

Changeset: 0dfe12b7a113
Author:    mchung
Date:      2016-03-15 12:01 -0700
URL:       http://hg.openjdk.java.net/jigsaw/jake/nashorn/rev/0dfe12b7a113

Bump jtreg requiredVersion to 4.2

! test/TEST.ROOT