hg: jdk/sandbox: 8211956: AppCDS crashes for some uses with JRuby

[chris.hegarty at oracle.com]

Changeset: 27df68106e57
Author:    jiangli
Date:      2018-10-15 15:21 -0400
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/27df68106e57

8211956: AppCDS crashes for some uses with JRuby
Summary: Make sure FileMapInfo::verify_mapped_heap_regions only verifies 'num' of spaces.
Reviewed-by: iklam

! src/hotspot/share/memory/filemap.cpp