YANG Parser (sometimes) has Source: null, making it hard to track which source model file an error is in

In some cases at least, when the yangtools yang parser fails, it does not say WHERE (while processing WHICH *.yang file) it fell over. Strangely, I have seen a case (see below) where it gives a line / column information, but not which model file.

I'll see if I can contribute a change to address this.

[main] ERROR org.opendaylight.yangtools.yang2sources.plugin.YangToSourcesProcessor - yang-to-sources: Unable to parse yang files from /home/vorburger/dev/ODL/git/controller/opendaylight/md-sal/samples/toaster-consumer/src/main/yang
java.lang.IllegalArgumentException: config:disable-osgi-service-registration is not a YANG statement or use of extension. Source: null:19:9
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:145)
at org.opendaylight.yangtools.yang.parser.impl.YangStatementParserListenerImpl.enterStatement(YangStatementParserListenerImpl.java:88)
at org.opendaylight.yangtools.antlrv4.code.gen.YangStatementParser$StatementContext.enterRule(YangStatementParser.java:113)
at org.antlr.v4.runtime.tree.ParseTreeWalker.enterRule(ParseTreeWalker.java:66)
at org.antlr.v4.runtime.tree.ParseTreeWalker.walk(ParseTreeWalker.java:49)
at org.antlr.v4.runtime.tree.ParseTreeWalker.walk(ParseTreeWalker.java:52)
at org.antlr.v4.runtime.tree.ParseTreeWalker.walk(ParseTreeWalker.java:52)
at org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangStatementSourceImpl.writeFull(YangStatementSourceImpl.java:94)
at org.opendaylight.yangtools.yang.parser.stmt.reactor.SourceSpecificContext.loadStatements(SourceSpecificContext.java:320)
at org.opendaylight.yangtools.yang.parser.stmt.reactor.BuildGlobalContext.loadPhaseStatements(BuildGlobalContext.java:206)
at org.opendaylight.yangtools.yang.parser.stmt.reactor.BuildGlobalContext.buildEffective(BuildGlobalContext.java:174)
at org.opendaylight.yangtools.yang.parser.stmt.reactor.CrossSourceStatementReactor$BuildAction.buildEffective(CrossSourceStatementReactor.java:105)
at org.opendaylight.yangtools.yang.parser.stmt.reactor.CrossSourceStatementReactor$BuildAction.buildEffective(CrossSourceStatementReactor.java:123)
at org.opendaylight.yangtools.yang2sources.plugin.YangToSourcesProcessor.processYang(YangToSourcesProcessor.java:169)
at org.opendaylight.yangtools.yang2sources.plugin.YangToSourcesProcessor.execute(YangToSourcesProcessor.java:93)
at org.opendaylight.yangtools.yang2sources.plugin.YangToSourcesMojo.execute(YangToSourcesMojo.java:116)