Should warn when unable to download parent ways/relations

[naoliv]

Have a node selected and then File → Download parent ways/relations
If for some reason there is an API/network issue, JOSM simply doesn't display anything.

We can see an error in console:

2018-09-06 09:56:47.101 GRAVE: org.openstreetmap.josm.io.OsmTransferException: Não foi possível conectar com o servidor OSM. Por favor, verifique sua conexão de internet.. Causa: java.net.SocketTimeoutException: connect timed out
org.openstreetmap.josm.io.OsmTransferException: Não foi possível conectar com o servidor OSM. Por favor, verifique sua conexão de internet.
	at org.openstreetmap.josm.io.OsmServerReader.getInputStreamRaw(OsmServerReader.java:197)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStreamRaw(OsmServerReader.java:137)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStreamRaw(OsmServerReader.java:121)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStream(OsmServerReader.java:85)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStream(OsmServerReader.java:68)
	at org.openstreetmap.josm.io.OsmServerBackreferenceReader.getReferringPrimitives(OsmServerBackreferenceReader.java:130)
	at org.openstreetmap.josm.io.OsmServerBackreferenceReader.getReferringWays(OsmServerBackreferenceReader.java:156)
	at org.openstreetmap.josm.io.OsmServerBackreferenceReader.parseOsm(OsmServerBackreferenceReader.java:237)
	at org.openstreetmap.josm.actions.downloadtasks.DownloadReferrersTask.downloadParents(DownloadReferrersTask.java:144)
	at org.openstreetmap.josm.actions.downloadtasks.DownloadReferrersTask.realRun(DownloadReferrersTask.java:190)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.doRealRun(PleaseWaitRunnable.java:95)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.run(PleaseWaitRunnable.java:143)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:514)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:844)
Caused by: java.net.SocketTimeoutException: connect timed out
	at java.base/java.net.PlainSocketImpl.socketConnect(Native Method)
	at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:400)
	at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:243)
	at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:225)
	at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:402)
	at java.base/java.net.Socket.connect(Socket.java:591)
	at java.base/sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:657)
	at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:177)
	at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
	at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
	at java.base/sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:265)
	at java.base/sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:372)
	at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:191)
	at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1181)
	at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1075)
	at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:177)
	at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:163)
	at org.openstreetmap.josm.tools.HttpClient.connect(HttpClient.java:145)
	at org.openstreetmap.josm.io.OsmServerReader.getInputStreamRaw(OsmServerReader.java:192)
	... 16 more

But nothing inside JOSM (which may give the wrong impression that the node doesn't have any related ways/relations).

In some other actions (like seeing the object history), JOSM properly displays a warning message that it was unable to connect:

Shouldn't/couldn't JOSM also display a message when a problem happens while trying to download the parent ways/relations from an object?

JOSM:

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2018-09-03 20:15:11 +0200 (Mon, 03 Sep 2018)
Revision:14221
Build-Date:2018-09-04 01:32:19
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (14221 pt_BR) Linux Debian GNU/Linux testing (buster)
Memory Usage: 6141 MB / 6144 MB (3986 MB allocated, but free)
Java version: 10.0.2+13-Debian-1, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1600x900, :0.1 1280x1024
Maximum Screen Size: 1600x1024
Java package: openjdk-10-jre:amd64-10.0.2+13-1
Java ATK Wrapper package: libatk-wrapper-java:all-0.33.3-21
VM arguments: [-Dawt.useSystemAAFontSettings=gasp]
Dataset consistency test: No problems found

[GerdP]

Closed as duplicate of #13177.