How did Thranduil knew about the 'infamous' Strider when the latter was only 10 during the Battle of the Five Armies?

On the last Hobbit movie, after the Battle of the Five Armies, Legolas tells Thranduil that he won't be coming home. The latter tells him to go to find the infamous son of Arathorn, that goes by the name of Strider.

But, the Battle of the Five Armies was fought on T.A. 2941 and Aragorn was only born on T.A. 2931.

How could Aragorn be such an infamous rogue in the age of only ten?

Sources: Aragorn, Battle of Five Armies and History of Middle Earth Timeline.