* Fixing bug triggered in an edge case. added integration test reproducing the issue 
 * this was causing an error during Archiving: "Fatal error: Cannot use object of type Piwik_DataTable_Row as array in /home/www/trunk/plugins/Actions/Actions.php on line 552"

git-svn-id: http://dev.piwik.org/svn/trunk@3768 59fd770c-687e-43c8-a1e3-f5a4ff64c105