For Bruce Niemeyer, the Chevron Corp. executive overseeing the company‚Äôs $15 billion expansion here, one question looms above all: Will we make money? Big oil companies including Chevron, Exxon Mobil Corp. and Royal Dutch Shell PLC are piling into the Permian Basin, the oil-rich region straddling Texas and New Mexico that is the epicenter of the second wave of U.S. shale drilling. Chevron and others say they…