hg: jdk/sandbox: 2 new changesets

[magnus.ihse.bursie at oracle.com]

Changeset: e25742fcb9a1
Author:    ihse
Date:      2020-04-28 18:18 +0200
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/e25742fcb9a1

Add -Xprefer:newer to microbenchmarks as well.

! make/test/BuildMicrobenchmark.gmk

Changeset: 7f326f4e67d1
Author:    ihse
Date:      2020-04-28 19:25 +0200
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/7f326f4e67d1

Possibly a better solution.

! make/common/JavaCompilation.gmk
! make/test/JtregGraalUnit.gmk