Democratic Sen. Kamala Harris of California announced on Saturday that she will make a decision about whether she will launch a presidential bid in 2020 by the end of this year. “It’s a very serious decision,” Harris told “Morning Joe” co-host Mika Brzezinski during an onstage conversation at the Know Your Value conference in San Francisco. “Over the holiday, I will make that decision with my family.” Harris, whose husband joined her in the audience, said she is keenly aware of the challenges a barrier-breaking campaign will entail. “Let’s be honest. It’s going to be ugly,” Harris said. “When you...