Exception when relaunching a security analysis

[jonenst]

• Do you want to request a feature or report a bug?
  bug

• What is the current behavior?
  There is an error popup window when relaunching a security analysis

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem
  Run a security analysis, then close the project, then reopen the project, then run a security analysis again.

• What is the expected behavior?
  No exception

• Please tell us about your environment:

  • PowSyBl Version: 2.5
  • OS Version: linux

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, spectrum, etc)

2019-05-06 18:34:53,163 ERROR [JavaFX Application Thread] c.p.g.u.GseUtil [GseUtil.java:138] com.powsybl.commons.PowsyblException: Variant index not set for current thread GSE-3
com.powsybl.commons.PowsyblException: Variant index not set for current thread GSE-3
	at com.powsybl.iidm.network.impl.ThreadLocalMultiVariantContext.getVariantIndex(ThreadLocalMultiVariantContext.java:23)
	at com.powsybl.iidm.network.impl.VariantManagerImpl.allowVariantMultiThreadAccess(VariantManagerImpl.java:183)
	at com.powsybl.security.afs.local.LocalSecurityAnalysisRunningService.run(LocalSecurityAnalysisRunningService.java:60)
	at com.powsybl.security.afs.SecurityAnalysisRunner.run(SecurityAnalysisRunner.java:82)
	at com.powsybl.gse.security.SecurityAnalysisExecutionTaskExtension.execute(SecurityAnalysisExecutionTaskExtension.java:43)
	at com.powsybl.gse.security.SecurityAnalysisExecutionTaskExtension.execute(SecurityAnalysisExecutionTaskExtension.java:21)
	at com.powsybl.gse.app.ProjectPane.lambda$executionTaskLaunch$28(ProjectPane.java:837)
	at com.powsybl.gse.util.GseUtil.lambda$execute$4(GseUtil.java:129)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)