/**
 * Placing container.  Extends {@link goog.ui.Container} by adding
 * the ability to place children at different content nodes.
 * @param {?goog.ui.Container.Orientation=} opt_orientation Container
 *     orientation; defaults to {@code VERTICAL}.
 * @param {?goog.ui.ContainerRenderer=} opt_renderer Renderer used to render or
 *     decorate the container; defaults to {@link goog.ui.ContainerRenderer}.
 * @param {?goog.dom.DomHelper=} opt_domHelper DOM helper, used for document
 *     interaction.
 * @extends {goog.ui.Component}
 * @constructor
 */
PlacingContainer = function(opt_orientation, opt_renderer, opt_domHelper) {
}