/**
  * {@inheritdoc}
  */
 public function removeCollectionFromProduct(ProductInterface $product, CollectionInterface $collection)
 {
     if (!($productCollection = $this->findOneBy(array('collection' => $collection, 'product' => $product)))) {
         return;
     }
     $product->removeProductCollection($productCollection);
     $this->delete($productCollection);
 }