Fix a possible division by zero (#634)
Fix a possible division by zero (#634)

* Fixed Division by zero when total execution time is 0ms

When you go to Symfony profiler -> Query Metrics and when Query time = 0ms there is an exception:
"An exception has been thrown during the rendering of a template ("Warning: Division by zero")."

[1/2] ContextErrorException: Warning: Division by zero 
in vendor\doctrine\doctrine-bundle\DataCollector\DoctrineDataCollector.php at line 232

[2/2] Twig_Error_Runtime: An exception has been thrown during the rendering of a template ("Warning: Division by zero")
in vendor\doctrine\doctrine-bundle\Resources\views\Collector\db.html.twig at line 157

* Fix division by zero in the data collector

mikeSimonson/DoctrineBundle,gencer/DoctrineBundle,nicolas-grekas/DoctrineBundle,OskarStark/DoctrineBundle,doctrine/DoctrineBundle,OskarStark/DoctrineBundle,fabpot/DoctrineBundle,nicolas-grekas/DoctrineBundle,fabpot/DoctrineBundle,mikeSimonson/DoctrineBundle,gencer/DoctrineBundle