Question: How do you stall real estate developers who are planning to bulldoze your favorite watering hole? Answer: Catch the bastards showering the street with asbestos and call the city on them. That’s what regulars say they did at The Littlest Bar, Downtown Crossing’s panic-room-sized Irish pub beneath the vacant parking garage at 47 Province Street. More than a year after the property was purchased by Boston’s Abbey Group, and nine months after the Littlest was slated to be leveled for construction of a massive 31-story luxury condo, spa and retail complex, the legendary hideout remains intact. "I was instrumental in delaying this thing," says Dave, a union worker who’s frequented the Littlest for 25 years. "Back in March, the new owners sent a couple of Mexican guys down here with cherry pickers and lightweight jackhammers to cut out asbestos panels.