Piwik\DataTable\Row::deleteMetadata PHP Method

    public function deleteMetadata($name = false)
    {
        if ($name === false) {
            $this->metadata = array();
            return true;
        }
        if (!isset($this->metadata[$name])) {
            return false;
        }
        unset($this->metadata[$name]);
        return true;
    }

 /**
  * @param Row $row
  * @param DataTable $dataTable
  * @param string $labelPrefix
  * @param bool $parentLogo
  */
 private function flattenRow(Row $row, $rowId, DataTable $dataTable, $labelPrefix = '', $parentLogo = false)
 {
     $label = $row->getColumn('label');
     if ($label !== false) {
         $label = trim($label);
         if ($this->recursiveLabelSeparator == '/') {
             if (substr($label, 0, 1) == '/') {
                 $label = substr($label, 1);
             } elseif ($rowId === DataTable::ID_SUMMARY_ROW && $labelPrefix && $label != DataTable::LABEL_SUMMARY_ROW) {
                 $label = ' - ' . $label;
             }
         }
         $label = $labelPrefix . $label;
         $row->setColumn('label', $label);
     }
     $logo = $row->getMetadata('logo');
     if ($logo === false && $parentLogo !== false) {
         $logo = $parentLogo;
         $row->setMetadata('logo', $logo);
     }
     /** @var DataTable $subTable */
     $subTable = $row->getSubtable();
     if ($subTable) {
         $subTable->applyQueuedFilters();
         $row->deleteMetadata('idsubdatatable_in_db');
     } else {
         $subTable = $this->loadSubtable($dataTable, $row);
     }
     $row->removeSubtable();
     if ($subTable === null) {
         if ($this->includeAggregateRows) {
             $row->setMetadata('is_aggregate', 0);
         }
         $dataTable->addRow($row);
     } else {
         if ($this->includeAggregateRows) {
             $row->setMetadata('is_aggregate', 1);
             $dataTable->addRow($row);
         }
         $prefix = $label . $this->recursiveLabelSeparator;
         $this->flattenDataTableInto($subTable, $dataTable, $prefix, $logo);
     }
 }