NullPointerException when converting layers

[richlv]

converted gpx layer to data layer, made some minor edits, converted it back to gpx layer. unexpectedly got a marker layer (no markers were present in the original gpx).

tried to convert the marker layer to data layer to examine it - exception

Revision: 8922
Repository Root: http://josm.openstreetmap.de/svn
Relative URL: ^/trunk
Last Changed Author: Don-vip
Last Changed Date: 2015-10-20 17:20:03 +0200 (Tue, 20 Oct 2015)
Build-Date: 2015-10-21 01:32:14
URL: http://josm.openstreetmap.de/svn/trunk
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last Changed Rev: 8922

Identification: JOSM/1.5 (8922 en) Linux openSUSE 13.2 (Harlequin) (x86_64)
Memory Usage: 434 MB / 683 MB (243 MB allocated, but free)
Java version: 1.8.0_60, Oracle Corporation, OpenJDK 64-Bit Server VM
VM arguments: [-Djava.net.useSystemProxies=true]

Plugins:
- ColumbusCSV (31241)
- InfoMode (31241)
- Mapillary (31550)
- PicLayer (31241)
- commons-imaging (31603)
- imagery_offset_db (31241)
- jna (31126)
- log4j (31231)
- pbf (31241)
- photo_geotagging (31241)
- photoadjust (31413)
- reverter (31241)

Last errors/warnings:
- E: java.lang.NullPointerException

java.lang.NullPointerException
	at org.openstreetmap.josm.gui.layer.gpx.ConvertToDataLayerAction.actionPerformed(ConvertToDataLayerAction.java:132)
	at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
	at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
	at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
	at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
	at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
	at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
	at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
	at java.awt.Component.processMouseEvent(Component.java:6535)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
	at java.awt.Component.processEvent(Component.java:6300)
	at java.awt.Container.processEvent(Container.java:2236)
	at java.awt.Component.dispatchEventImpl(Component.java:4891)
	at java.awt.Container.dispatchEventImpl(Container.java:2294)
	at java.awt.Component.dispatchEvent(Component.java:4713)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
	at java.awt.Container.dispatchEventImpl(Container.java:2280)
	at java.awt.Window.dispatchEventImpl(Window.java:2750)
	at java.awt.Component.dispatchEvent(Component.java:4713)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
	at java.awt.EventQueue.access$500(EventQueue.java:97)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.awt.EventQueue$3.run(EventQueue.java:703)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
	at java.awt.EventQueue$4.run(EventQueue.java:731)
	at java.awt.EventQueue$4.run(EventQueue.java:729)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

[Don-vip]

Closed as duplicate of #12059.