After step 37 of the Legion-Broken Shore(10+) module, you are told to speak to the Kirin Tor Emissary to be teleported to Dalaran. The waypoint arrow points to the first room on the left as you enter Stormwind Keep. However, the Emmisary is now located in the lower floor of the Mages tower just before you exit onto the ramp.
It took a while to find him. LoL. Only got attacked by a scourge once trying to find him. Could have been worse.