Christmas has not been celebrated at Chicago’s Marshall Field’s department stores since 2005, but mention the name to just about any Windy City native, and it will plunge them back into the childhood wonder of the flagship downtown shopping emporium during the holiday season. Gazing up at the towering evergreen of the Walnut Room, glittering ornaments weighing on its boughs. Winding through lines for Cozy Cloud Cottage, waiting for a moment with Santa. Marveling at the elaborate holiday windows along …