In MLB, if there are runners on 2nd base and 3rd base and the game is tied, and the batter hits a ground rule double, how is it scored?

So, the score is tied 1-1 with the home team up in the bottom of the 9th and the hitter is up with two runners in scoring positions. The hitter rips one down the line and it bounces into the stands for a ground rule double. Does the hitter get credited with a double? Does both runners score, so the hitter gets two Runs Batted In? If you hit a home run with the bases loaded and you need one run to win, you get all four, but does that same idea apply to ground rule doubles?