Sets the sticky-at-top-of-list property of a node to 1.
Drupal\node\Node $node: A node entity.
$context: (optional) Array of additional information about what triggered the action. Not used for this action.
function node_make_sticky_action(Node $node, $context = array()) {
  $node->sticky = NODE_STICKY;
  watchdog('action', 'Set @type %title to sticky.', array(
    '@type' => node_get_type_label($node),
    '%title' => $node
      ->label(),
  ));
}