[8u] backport of 8026796: Make replace_in_map() on parent maps generic

[Roland Westrelin]

8u backport request. The change was pushed to jdk9 in June.

The change doesn’t apply cleanly to 8u.
https://bugs.openjdk.java.net/browse/JDK-8026796
http://hg.openjdk.java.net/jdk9/hs-comp/hotspot/rev/e38bb04f030d

Webrev with the change merged into 8u:
http://cr.openjdk.java.net/~roland/8026796/webrev.03/

Roland.