Since her 2016 co-write and vocal feature on Mike Perry’s tropical-tinged “The Ocean,” SHY Martin (born Sara Hkellström) has quietly dominated the dance floor in countries well beyond her native Sweden. The singer/songwriter draws big hooks out of the most delicate vocals and melodies, translating into breezy, feel-good hits for Kygo & Ellie Goulding (“First Time”), The Chainsmokers (“All We Know”), and herself (“Make Us Never Happen”).