NEW YORK — A Gillette ad for men invoking the #MeToo movement is sparking intense online backlash, with accusations that it talks down to men and groups calling for a boycott. But Gillette says it doesn’t mind sparking a discussion. Since it debuted Monday, the Internet-only ad has garnered nearly 19 million views on YouTube, Facebook and Twitter — a level of buzz that any brand would covet. The two-minute ad from Procter & Gamble’s razor brand shows men and boys engaging in bullying and sexual harassment and encourages men to “say the right thing” and “act the right way.” Taking on bullying, sexual harassment and toxic masculinity is a big task for a razor brand.