As reported in forums
Error: Argument 1 passed to Piwik\DataAccess\LogQueryBuilder\JoinTables::__construct() must be an instance of Piwik\Plugin\LogTablesProvider, null given, called in ....\core\DataAccess\LogQueryBuilder.php on line 46
Actually I don't know how this error could occur - when could the Dependency injected object be null? if anyone has some idea...