Question: Which American singer and guest star on Austin & Ally performed the song It's Goin' Down in the 2017 film Descendants 2?
Sentence (from "It's Goin' Down (Descendants song)"): "It's Goin' Down" is a song from Disney Channel's 2017 television film "Descendants 2", whose music and lyrics were composed by Antonina Armato, Tim James, Tom Sturges and Adam Schmalholz.
Relevant evidence: Yes