Backport of:
https://git.eclipse.org/r/#/c/80818/
to R4_6.

Hand-written (instead of cherry picking) as instance-of was never
introduced in maintenance.

Change-Id: I7cb40cc4069e947697b74927ade1d9b628252fff
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=497812
Signed-off-by: Leo Ufimtsev <lufimtse@redhat.com>