add DijitRegistry#getParent

[k2s]

pls. add DijitRegistry#getParent for compatibility with dijit._KeyNavContainer

this is the code in dijit._KeyNavContainer

        childSelector: function(/*DOMNode*/ node){
            // Implement _KeyNavMixin.childSelector, to identify focusable child nodes.
            // If we allowed a dojo/query dependency from this module this could more simply be a string "> *"
            // instead of this function.

            var node = registry.byNode(node);
            return node && node.getParent() == this;
        }

Grid is received from registry, but it doesn't provide getParent(). Any _WidgetBase descendant would provide getParent().

[kfranqueiro]

This has been merged in b2c5ef8. Thanks for the contribution!