Wrong multipolygon validation when filter is applied

[naoliv]

Open the attached example file and validate.
We don't see anything related with an open/unclosed multipolygon (as it should be).

Now apply a filter with highway, mark both E and H (so the highway part gets hidden) and validate it again: we can now see a Multipolygon is not closed error.

Probably the validator should ignore filtered objects? (since, for this case, the multipolygon is in fact closed)

JOSM:

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2019-07-20 23:09:36 +0200 (Sat, 20 Jul 2019)
Revision:15260
Build-Date:2019-07-21 01:31:02
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (15260 en) Linux Debian GNU/Linux bullseye/sid
Memory Usage: 365 MB / 6144 MB (180 MB allocated, but free)
Java version: 13-ea+28-Debian-1, Debian, OpenJDK 64-Bit Server VM
Screen: :0.0 1600x900, :0.1 1280x1024
Maximum Screen Size: 1600x1024
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-22
libcommons-compress-java: libcommons-compress-java:all-1.18-2
libcommons-logging-java: libcommons-logging-java:all-1.2-2
fonts-noto: fonts-noto:-
liboauth-signpost-java: liboauth-signpost-java:all-1.2.1.2-2
VM arguments: [-Dawt.useSystemAAFontSettings=gasp]
Program arguments: [--language=en]
Dataset consistency test: No problems found

Plugins:
+ FixAddresses (34977)
+ OpeningHoursEditor (34977)
+ PicLayer (35030)
+ SimplifyArea (34977)
+ apache-commons (34908)
+ apache-http (34908)
+ buildings_tools (34982)
+ ejml (35049)
+ geojson (124)
+ geotools (34908)
+ http2 (35062)
+ jaxb (35014)
+ jna (34908)
+ jts (35064)
+ log4j (34908)
+ mbtiles (v2.5.0)
+ measurement (35051)
+ merge-overlap (35072)
+ opendata (34997)
+ poly (34991)
+ reverter (34999)
+ tag2link (35070)
+ tageditor (34977)
+ todo (30306)
+ turnlanes-tagging (281)
+ turnrestrictions (34977)
+ undelete (34977)
+ utilsplugin2 (34977)
+ wikipedia (v1.1.1)

[GerdP]

don't ignore hidden ways when building multipolygon