A Santa Ana man has been convicted of murder in a gang-related shooting of two teens the afternoon of October 2, 2015 in Garden Grove. Adrian De La Riva, 27, was found guilty on Feb. 14 of first degree murder, with sentencing enhancements for criminal street gang activity, attempted murder, attempted premeditated murder, and for vicarious discharging of a firearm causing great bodily injury, court records show. A man in a Jeep had fired several rounds at two teens, shooting a 16-year-old in the upper torso and 17-year-old Francisco Salgado in the upper arm. The 16-year-old died at the scene,…