* Client-Side Metrics Include
* Wiki: https://tiny.amazon.com/cpso0wg6
* Needs to be included at the top of pages because it tracks latency--
* ue_t0 needs to be as close to body load as possible.
* - ue.tag maps to URLType dimension of OnlineQueryLog in PMET. Because we cannot add
* custome data to other dimensions in PMET through CSM, we are replicating it thrice to
* cover each store, page type, and the intersections of the two.
* - Whitelists are listed in the usage guide:
If ever you should awaken from a troubled sleep to find yourself in a barren place, if ever you should find yourself wondering who you are, where you came from, or how you came to be running for your very life through a labyrinth of shadows and murderous beasts, if ever you come to feel that your every footfall is guided by a power and a menace which drives you toward your destruction for the sake of its own hideous amusement... Well...