Unsets value in this config object.
string $key: Name of the key whose value should be unset.
Drupal\Core\Config\Config The configuration object.
public function clear($key) {
$parts = explode('.', $key);
if (count($parts) == 1) {
unset($this->data[$key]);
}
else {
NestedArray::unsetValue($this->data, $parts);
}
$this
->resetOverriddenData();
return $this;
}