/**
  * Find common attributes
  * Common attributes are:
  *   - not unique (and not identifier)
  *   - without value AND link to family
  *   - with value
  *
  * @param array $productIds
  *
  * @return \Pim\Bundle\CatalogBundle\Model\AbstractAttribute[]
  */
 public function findCommonAttributes(array $productIds)
 {
     $attributeIds = $this->massActionRepository->findCommonAttributeIds($productIds);
     return $this->attributeRepository->findWithGroups(array_unique($attributeIds), array('conditions' => ['unique' => 0]));
 }