A function or library to get total heirloom/buff bonus xp?
 

Currently the only way I know how to figure out a player's bonus xp is to manually examine their equipment, gems, and buffs for specific ones that provide increased xp.

It seems like it would be quite expensive to hook into aura changes and gear equips solely to keep this information up to date, so I wondered if there was an easier way to do this? Or barring that, has someone already gone through the work of creating a library for this?