This quest was marked obsolete by Blizzard and cannot be obtained or completed.
Find the Half Pendant of Aquatic Agility and the Half Pendant of Aquatic Endurance. Speak with the residents of Moonglade to learn clues as to where these items may be located.
Form the Pendant of the Sea Lion from the two pendant halves. You need to be in proximity of the Shrine of Remulos to do this.
Bring the joined pendant to Dendrite Starblaze in the village of Nighthaven, Moonglade.
For the second trial, you'll need the two halves that make the Pendant of the Sea Lion. One half draws power from the agility of the sea lion aspect, gliding through water; the other draws power from the incredible endurance of the sea lion aspect. Druids draw on both these traits equally to embody the aspect of their aquatic form.
Speak with the locals of Moonglade to learn where the parts may lie, and bring both here to join them together. Once formed, take the pendant to Dendrite Starblaze.
Have you formed your pendant for me to inspect, <name>? If you need help in locating the parts, try asking the local populace for information. Not only will you find what you seek, but it will give you a reason to explore this wondrous and sacred glade.
You've completed the Trial of the Sea Lion, <name> - congratulations.
Each task in acquiring the pendant shows that both agility and endurance are necessary to act in harmony with what you desire to do underwater. Neither can exist without the other, and both cannot be done without your willingness to embrace the aspect of the sea lion.
Remember these lessons well, and count on them once you have gained your aquatic form.