Adding a magazine recipe to groceries includes headings and hides the picker

From a magazine recipe, Add to list can include section headings such as WET INGREDIENTS as shopping items, and the magazine can cover the ingredient picker so its controls cannot be used. Keep the saved ingredient order, leave headings out of groceries, and return to the same magazine page after adding or cancelling. Reproduced in Chromium and WebKit during the September bug-fix pass.