Description of problem:
When uploading po file from web UI, an exception is thrown

Version-Release number of selected component (if applicable):
3.7.0 to 3.8.0-SNAPSHOT

How reproducible:
Always

Steps to Reproduce:
1. Go to a gettext/podir project, version, settings, Document 
2. At the project version screen, select the language 
3. Click the inverted caret on the document to show the menu 
4. Select Upload Translations 
5. Select a po file
6. Click Upload 

Actual results:
Exception (array out of bounds exception) 

Expected results:
po file is uploaded.

Additional info:
ERROR [org.jboss.seam.exception.Exceptions] (default task-23) handled and logged exception: javax.servlet.ServletException: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0 
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:606) [jsf-api-2.1.29-01.jar:2.1] 
at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:86) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:130) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:164) [javamelody-core-1.52.0.jar:1.52.0] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.tuckey.web.filters.urlrewrite.RuleChain.handleRewrite(RuleChain.java:176) [urlrewritefilter-4.0.4.jar:4.0.4] 
at org.tuckey.web.filters.urlrewrite.RuleChain.doRules(RuleChain.java:145) [urlrewritefilter-4.0.4.jar:4.0.4] 
at org.tuckey.web.filters.urlrewrite.UrlRewriter.processRequest(UrlRewriter.java:92) [urlrewritefilter-4.0.4.jar:4.0.4] 
at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:389) [urlrewritefilter-4.0.4.jar:4.0.4] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:60) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:86) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.zanata.seam.interceptor.MonitoringWrapper.doFilter(MonitoringWrapper.java:67) [classes:] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.zanata.servlet.GWTCacheControlFilter.doFilter(GWTCacheControlFilter.java:61) [classes:] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.zanata.servlet.MDCInsertingServletFilter.doFilter(MDCInsertingServletFilter.java:70) [classes:] 
at io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:60) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:132) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:85) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78) 
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.security.handlers.AuthenticationConstraintHandler.handleRequest(AuthenticationConstraintHandler.java:51) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.ServletSecurityConstraintHandler.handleRequest(ServletSecurityConstraintHandler.java:56) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:58) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:72) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.security.handlers.SecurityInitialHandler.handleRequest(SecurityInitialHandler.java:76) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61) 
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:274) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:253) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:80) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:172) [undertow-servlet-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.server.Connectors.executeRootHandler(Connectors.java:199) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:774) [undertow-core-1.2.7.Final.jar:1.2.7.Final] 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_79] 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_79] 
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.7.0_79] 
Caused by: javax.faces.el.EvaluationException: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0 
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:101) [jsf-api-2.1.29-01.jar:2.1] 
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:101) [jsf-impl-2.1.29-01.jar:2.1.29-01-SNAPSHOT] 
at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jsf-api-2.1.29-01.jar:2.1] 
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:786) [jsf-api-2.1.29-01.jar:2.1] 
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1251) [jsf-api-2.1.29-01.jar:2.1] 
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.29-01.jar:2.1.29-01-SNAPSHOT] 
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.29-01.jar:2.1.29-01-SNAPSHOT] 
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.29-01.jar:2.1.29-01-SNAPSHOT] 
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jsf-api-2.1.29-01.jar:2.1] 
... 59 more 
Caused by: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0 
at java.util.ArrayList.rangeCheck(ArrayList.java:635) [rt.jar:1.7.0_79] 
at java.util.ArrayList.get(ArrayList.java:411) [rt.jar:1.7.0_79] 
at org.zanata.action.VersionHomeAction.uploadTranslationFile(VersionHomeAction.java:981) [classes:] 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_79] 
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_79] 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_79] 
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_79] 
at org.jboss.seam.util.Reflections.invoke(Reflections.java:22) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:32) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:28) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:79) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:44) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.security.SecurityInterceptor.aroundInvoke(SecurityInterceptor.java:163) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.core.SynchronizationInterceptor.aroundInvoke(SynchronizationInterceptor.java:35) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:196) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:114) [jboss-seam-2.3.1.Final.jar:2.3.1.Final] 
at org.zanata.action.VersionHomeAction_$$_javassist_seam_84.uploadTranslationFile(VersionHomeAction_$$_javassist_seam_84.java) [classes:] 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_79] 
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_79] 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_79] 
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_79] 
at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:335) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:280) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at org.jboss.el.parser.AstMethodSuffix.getValue(AstMethodSuffix.java:59) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at org.jboss.el.parser.AstMethodSuffix.invoke(AstMethodSuffix.java:65) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at org.jboss.el.parser.AstValue.invoke(AstValue.java:96) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at org.jboss.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6] 
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.29-01.jar:2.1.29-01-SNAPSHOT] 
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:87) [jsf-api-2.1.29-01.jar:2.1] 
... 67 more