Slow auto-fix with a lot of objects on map

[naoliv]

When there is a big area and/or a lot of objects, JOSM is slow to auto-fix some validation issues.
With the attached file, validate it and locate the only "area is unnecessary for landuse" problem. Select it and click to fix.
Note how long (and how much CPU it takes) to only remove an area=yes.

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2014-10-24 01:34:04
Last Changed Author: Klumbumbus
Revision: 7647
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Relative URL: ^/trunk
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2014-10-23 21:00:12 +0200 (Thu, 23 Oct 2014)
Last Changed Rev: 7647

Identification: JOSM/1.5 (7647 en) Linux Debian GNU/Linux unstable (sid)
Memory Usage: 351 MB / 4029 MB (101 MB allocated, but free)
Java version: 1.7.0_65, Oracle Corporation, OpenJDK 64-Bit Server VM
Java package: openjdk-7-jre:amd64-7u71-2.5.3-1
VM arguments: [-Dawt.useSystemAAFontSettings=on]
Dataset consistency test: No problems found

Plugins:
- AddrInterpolation (30737)
- Create_grid_of_ways (30762)
- FixAddresses (30737)
- ImageryCache (30738)
- OpeningHoursEditor (30737)
- PicLayer (30762)
- SimplifyArea (30762)
- buildings_tools (30762)
- download_along (30762)
- editgpx (30737)
- geotools (30762)
- graphview (30762)
- jts (30762)
- measurement (30737)
- merge-overlap (30762)
- notes (v0.9.4)
- opendata (30762)
- pdfimport (30737)
- poly (30738)
- reverter (30737)
- tagging-preset-tester (30736)
- todo (29154)
- turnrestrictions (30762)
- undelete (30762)
- utilsplugin2 (30762)

[Don-vip]

Closed as duplicate of #10101.
We're already doing everything we can easily do. The kind of optimization I have added in r7656 is already implemented. It's just linked to the general performance problem with large datasets. Closing it as a duplicate of the other one, sorry...