When the NFL last week gave its approval for the St. Louis Rams to return to L.A. and begin a second life as the Los Angeles Rams, and let the San Diego Chargers move in, it put into motion a play for naming rights to their home, an 80,000-seat stadium and 298-acre entertainment complex scheduled to open for the 2019 season. That will be the biggest such deal in naming rights history. Among the potential Los Angeles-based companies: Hyundai, Farmers Insurance, Live Nation, DirecTV and even the Walt Disney Co.