SAN FRANCISCO — Sen. Dianne Feinstein has dominated California politics for more than a quarter of a century. But facing blistering criticism that she’s out of touch with the progressive left following her recent comments about President Donald Trump and DACA, it’s increasingly looking like the Democratic lawmaker will face a major primary challenge if she runs for a fifth full term.Feinstein, the oldest member of the Senate, has been the target of sustained liberal criticism since January.