In a legal dispute that is nearly identical to a case playing out in LoDo, a local landlord is accusing 7-Eleven of allowing one of its most prominent Boulder stores to become a homeless hangout, drug market and crime scene, harming the landlord’s leasing efforts. Urban Frontier, a Denver firm, owns the former Flatirons Theatre at 1091 13th St., near the University of Colorado. The building is now a 9,300-square-foot retail space. It is also “a magnet for homeless people,” according to a lawsuit that Urban Frontier filed against 7-Eleven’s corporate office on Jan.