Losing valid values when autofixing in some tests

[naoliv]

Open the attached file and note that we have an object with amenity=fuel + brand=bah + Brand=foo
Validate and see a warning Key 'Brand' looks like 'brand'. - Misspelled property key with an option to fix.
Click on fix and see the new value brand=foo (it was brand=bah).

If possible, the test should verify for the new key:

• if present, just warn, without fix
• if not, offer a fix.

I guess that it should also be verified if there are more tests like this one, to see if the new key is already present.

JOSM:

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2016-01-08 10:43:21 +0100 (Fri, 08 Jan 2016)
Build-Date:2016-01-09 02:34:54
Revision:9345
Relative:URL: ^/trunk

Identification: JOSM/1.5 (9345 pt_BR) Linux Debian GNU/Linux unstable (sid)
Memory Usage: 1228 MB / 3641 MB (619 MB allocated, but free)
Java version: 1.8.0_72-internal-b05, Oracle Corporation, OpenJDK 64-Bit Server VM
VM arguments: [-Dawt.useSystemAAFontSettings=on]

Dataset consistency test:
[WARN - NO NODES] Way {Way id=387220682 version=1 VT nodes=[{Node id=3905388832 version=1 V lat=-23.5578016,lon=-46.4762442}]} has only one node


Plugins:
- AddrInterpolation (31772)
- Create_grid_of_ways (31772)
- FastDraw (31895)
- FixAddresses (31772)
- OpeningHoursEditor (31772)
- PicLayer (31895)
- SimplifyArea (31895)
- apache-commons (31895)
- buildings_tools (31895)
- download_along (31772)
- editgpx (31772)
- ejml (31895)
- geotools (31895)
- graphview (31895)
- jts (31772)
- log4j (31895)
- measurement (31895)
- merge-overlap (31772)
- opendata (31937)
- pdfimport (31895)
- photo_geotagging (31895)
- poly (31772)
- reverter (31926)
- tagging-preset-tester (31895)
- todo (29154)
- turnrestrictions (31895)
- undelete (31895)

[simon04]

In 9382/josm:

fix #12329 - Tag checker: Losing valid values when auto-fixing in some tests