He's specifically asking about learning theory which is a subfield of machine learning, along the lines of work you'll see at COLT, using concentration bounds,

He's specifically asking about learning theory which is a subfield of machine learning, along the lines of work you'll see at COLT, using concentration bounds, VC theory, and Rademacher complexity. PRML, Murphy, ESL, the Deep Learning book, and the RL introduction are more like what you'd see at ICML or ICLR.