function didGetClassName(className)
        {
            if (!className)
                return null;
            var constructorNodes = this.topLevelNodes();
            for (var i = 0; i < constructorNodes.length; i++) {
                var parent = constructorNodes[i];
                if (parent._name === className)
                    return parent.populateNodeBySnapshotObjectId(parseInt(id, 10)).then(didPopulateNode.bind(this));
            }
            // There are no visible top level nodes with such className.
            return null;
        }
@param {?string} className
@return {?Promise<?WebInspector.HeapSnapshotGridNode>}
@this {WebInspector.HeapSnapshotConstructorsDataGrid}