Support opening shapefiles in ESPG:3857

[naoliv]

While noticing that JOSM uses the Mercator projection (ESPG:3857) I exported a shapefile (from QGIS) using the same projection, but JOSM fails to detect it and offers to fallback to ESPG:4326.

Since JOSM already support and uses it, couldn't it also poperly detect shapefiles using this projection?

Also, if accepting to fallback, coordinates seem to be all messed up (for example, node at 2422568°52'13.5"S, 5320119°37'09.3"W)

The file is attached.

JOSM

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2016-05-30 02:06:54 +0200 (Mon, 30 May 2016)
Build-Date:2016-05-30 01:32:45
Revision:10301
Relative:URL: ^/trunk

Identification: JOSM/1.5 (10301 en) Linux Debian GNU/Linux testing (stretch)
Memory Usage: 247 MB / 10206 MB (108 MB allocated, but free)
Java version: 1.8.0_91-8u91-b14-2-b14, Oracle Corporation, OpenJDK 64-Bit Server VM
VM arguments: [-Dawt.useSystemAAFontSettings=on]

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