Fix history tab: - invalid bug count for oldest version - javascript error with non historized xml data
Fix history tab:
- invalid bug count for oldest version
- javascript error with non historized xml data


git-svn-id: e7d6bde23f017c9ff4efd468d79d66def666766b@7846 eae3c2d3-9b19-0410-a86e-396b6ccb6ab3

sewe/spotbugs,spotbugs/spotbugs,spotbugs/spotbugs,KengoTODA/spotbugs,johnscancella/spotbugs,spotbugs/spotbugs,johnscancella/spotbugs,KengoTODA/spotbugs,KengoTODA/spotbugs,johnscancella/spotbugs,spotbugs/spotbugs,sewe/spotbugs,sewe/spotbugs,spotbugs/spotbugs,sewe/spotbugs,johnscancella/spotbugs,KengoTODA/spotbugs