Save As "Validation Error Files (*.xml) stores osm data instead of errors

[GerdP]

What steps will reproduce the problem?

1. Have a list of errors in the validator panel
2. Save As, type xyz as file name
3. Select "Validation Error Files (*.xml)" from the "Files of type" list

What is the expected result?

a file xyz.xml with the errors

What happens instead?

a file xyz.xml with the osm data

Please provide any additional information below. Attach a screenshot if possible.

I tried to find out why the OsmDataLayer has the field validationErros and found this bug.
Problem is that xml is also a valid extension for the osm exporter, and this takes over.
Somehow the information of the wanted exporter is lost in
checkFileAndConfirmOverWrite(AbstractFileChooser fc, String extension).

Build-Date:2019-01-08 12:58:11
Revision:14663
Is-Local-Build:true

Identification: JOSM/1.5 (14663 SVN en) Windows 10 64-Bit
OS Build number: Windows 10 Home 1803 (17134)
Memory Usage: 697 MB / 1792 MB (388 MB allocated, but free)
Java version: 1.8.0_191-b12, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: \Display0 1920x1080
Maximum Screen Size: 1920x1080
VM arguments: [-agentlib:jdwp=transport=dt_socket,suspend=y,address=localhost:60104, -ea, -javaagent:D:\portable_prgs\eclipse\configuration\org.eclipse.osgi\237\0\.cp\lib\javaagent-shaded.jar, -Dfile.encoding=UTF-8]
Program arguments: [--debug]
Dataset consistency test: No problems found

Plugins:
+ FastDraw (34510)
+ apache-commons (34506)
+ buildings_tools (34807)
+ download_along (34503)
+ editgpx (34751)
+ ejml (34389)
+ geotools (34513)
+ gpxfilter (34506)
+ jaxb (34506)
+ jts (34524)
+ measurement (34529)
+ o5m (34405)
+ opendata (34805)
+ pbf (34576)
+ poly (34546)
+ reltoolbox (34788)
+ reverter (34552)
+ utilsplugin2 (34793)

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- W: Failed to locate resource '/README'.
- W: Failed to locate resource '/CONTRIBUTION'.
- W: Failed to locate resource '/LICENSE'.

[simon04]

In 14667/josm:

see #17185 - Allow to save active ValidatorLayer

[simon04]

In 14668/josm:

fix #17185 - Do not offer unsupported file types for saving OsmDataLayer