LOS ANGELES — The combined powers of superheroes, the Pixar brand and a drought of family-friendly films helped “Incredibles 2” become the best animated opening of all time, the biggest PG-rated launch ever and the 8th highest film launch overall. Disney estimated Sunday that the film earned $180 million in its first weekend in North American theaters — far surpassing industry analysts’ loftiest expectations which had the film pegged for a $120 to $140 million debut. The previous animation record-holder was another Pixar sequel, “Finding Dory,” which had a $135 million launch in 2016.