Freddie Ljungberg netted the winner, with Jari Litmanen bagging the consolation goal for the home side.
Henry is Arsenal's all-time top goalscorer with 228 goals. He scored 175 of those goals in the Premier League.
Saka has beaten a number of other Arsenal legends to being the youngest to hit 50 Premier League goals.
Theo Walcott was 26 years and 69 days old when he did it in 2015 against West Bromwich Albion.