During polarizing times, musicians find they often need to walk a fine line.While the Goo Goo Dolls aren’t known for socially conscious songs, front man John Rzeznik felt compelled to weigh in on the state of things. The rocking title track to the recent EP, “You Should Be Happy,” finds him singing about saving “what’s left of the American dream.”“An opinion has become poison in this country,” affirmed bassist Robby Takac, who co-founded the Buffalo pop/rock band with Rzeznik in 1985. “You’re going to lose half your support if you [take] one side or the other. Personally, I just think you live