/**
* Updates the current frame of the stack.
*
* @param array &$element
* The element of the render array that has just been rendered. The stack
* frame for this element will be updated with the bubbleable rendering
* metadata of this element.
*/
public function update(&$element)
{
// The latest frame represents the bubbleable metadata for the subtree.
$frame = $this->pop();
// Update the frame, but also update the current element, to ensure it
// contains up-to-date information in case it gets render cached.
$updated_frame = BubbleableMetadata::createFromRenderArray($element)->merge($frame);
$updated_frame->applyTo($element);
$this->push($updated_frame);
}
/**
* {@inheritdoc}
*/
public function addAttachments(array $attachments)
{
$this->attachments = BubbleableMetadata::mergeAttachments($this->attachments, $attachments);
return $this;
}
