Explore > Revenue, Production, GDP: wire up (or nix) device-specific toggle buttons

[shawnbot]

Currently the explore data sections we've implemented have two buttons in the DOM to toggle the visibility of the filters, but only the first one (the desktop-specific one) works because I didn't consider the need for two of them. @gemfarmer, we either need to figure out how to have only one button (potentially tricky CSS) or to wire up two buttons that mirror one another's states (tricky JS).