Review Coverage Report has an error when hovering over committer in Individual Committer Stats panel

Steps to reproduce

1. Navigate to Repositories >> reponame >> Reports >> Review Coverage
2. Look for the day that have commit
   The committer will be shown in Individual Committer Stats panel
3. Hover over the committer will have a message "Retrieving undefined ..."
   In the log, there will be a lot of the following error:

   2013-10-03 21:06:36,669 WARN  [qtp650484437-128 ] fisheye.app ReviewCoverageServlet-sendError - [REVIEW-COVERAGE] Error encountered whilst producing a Review Coverage Report : The path /undefined in repository test is not correct.
   2013-10-03 21:06:36,670 ERROR [qtp650484437-128 ] fisheye TotalityFilter-logExceptionDetails - Exception "The path /undefined in repository test is not correct." (java.lang.RuntimeException) while processing "/plugins/servlet/review-coverage/test/undefined" (Referer:"http://localhost:8060/plugins/servlet/review-coverage/test/")
   java.lang.RuntimeException: The path /undefined in repository test is not correct.
   	at com.atlassian.fisheye.reports.ReviewCoverageServlet.sendError(ReviewCoverageServlet.java:205)
   	at com.atlassian.fisheye.reports.ReviewCoverageServlet.doGet(ReviewCoverageServlet.java:144)
   	at javax.servlet.http.HttpServlet.service(HttpServlet.java:735)
   	at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
   	at com.atlassian.plugin.servlet.DelegatingPluginServlet.service(DelegatingPluginServlet.java:42)
   	at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
   	at com.atlassian.fisheye.plugin.servlet.FisheyeServletModuleContainerServlet.service(FisheyeServletModuleContainerServlet.java:61)
   	at javax.servlet.http.HttpServlet.service(HttpServlet.java:848)
   	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:669)
   	at org.eclipse.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1526)