Two Dimensional Filter Statistics Gadget fails when YAxis is a Custom Field restricted to certain issue types

2016-03-30 08:55:25,931 ERROR /rest/gadget/1.0/statistics [c.a.p.r.c.error.jersey.ThrowableExceptionMapper] Uncaught exception thrown by REST service: com.atlassian.jira.issue.issuetype.IssueTypeImpl cannot be cast to org.ofbiz.core.entity.GenericValue
java.lang.ClassCastException: com.atlassian.jira.issue.issuetype.IssueTypeImpl cannot be cast to org.ofbiz.core.entity.GenericValue
	at com.atlassian.jira.util.ofbiz.GenericValueUtils.transformToStringIds(GenericValueUtils.java:67)
	at com.atlassian.jira.util.ofbiz.GenericValueUtils.transformToStringIdsList(GenericValueUtils.java:86)
	at com.atlassian.jira.issue.customfields.statistics.AbstractCustomFieldStatisticsMapper.getSearchContextFromValue(AbstractCustomFieldStatisticsMapper.java:94)
	at com.atlassian.jira.issue.customfields.statistics.AbstractCustomFieldStatisticsMapper.getSearchUrlSuffix(AbstractCustomFieldStatisticsMapper.java:50)
	at com.atlassian.jira.dashboarditem.statistics.service.statistics.searcher.StatisticsSearcher$StatisticMapperWrappingSearchRequestAppender.appendInclusiveSingleValueClause(StatisticsSearcher.java:173)
	at com.atlassian.jira.dashboarditem.statistics.service.statistics.searcher.StatisticsSearcher.completeOneDimensionalSearch(StatisticsSearcher.java:132)
	at com.atlassian.jira.dashboarditem.statistics.service.statistics.searcher.StatisticsSearcher.completeOneDimensionalSearch(StatisticsSearcher.java:81)
	at com.atlassian.jira.dashboarditem.statistics.service.statistics.StatisticsServiceImpl.aggregateOneDimensionalStats(StatisticsServiceImpl.java:98)
	at com.atlassian.jira.dashboarditem.statistics.rest.StatisticsResource.oneDimensionalSearchWithJql(StatisticsResource.java:130)
	at com.atlassian.jira.dashboarditem.statistics.rest.StatisticsResource.oneDimensionalSearchForFilter(StatisticsResource.java:109)
	at com.atlassian.jira.dashboarditem.statistics.rest.StatisticsResource.oneDimensionalSearch(StatisticsResource.java:77)
	... 2 filtered
	at java.lang.reflect.Method.invoke(Method.java:497)
	... 18 filtered
	at com.atlassian.plugins.rest.module.RestDelegatingServletFilter$JerseyOsgiServletContainer.doFilter(RestDelegatingServletFilter.java:178)
	... 1 filtered
	at com.atlassian.plugins.rest.module.RestDelegatingServletFilter.doFilter(RestDelegatingServletFilter.java:73)
	... 110 filtered
	at com.atlassian.plugins.rest.module.servlet.RestSeraphFilter.doFilter(RestSeraphFilter.java:40)
	... 72 filtered
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)

    protected SearchContext getSearchContextFromValue(Object value) {
        [...]

        List associatedIssueTypes = customField.getAssociatedIssueTypes();  // <-- notice the generic List?
        if (associatedIssueTypes != null && !associatedIssueTypes.isEmpty() && associatedIssueTypes.get(0) != null) {
            issueTypeIds = GenericValueUtils.transformToStringIdsList(associatedIssueTypes);  //  <-- Oops! customField.getAssociatedIssueTypes now returns a List<IssueType>, not a List<GenericValue> anymore. So you cannot call GenericValueUtils.transformToStringIdsList on it. But since associatedIssueTypes is a List and not a List<GenericValue>, you don't see the error at compilation time...
        }

        [...]
    }