With its star-studded cast of attendees, its plush setting at the famed Cipriani Wall Street, and its strict no-media rules, the Clinton Foundation’s annual gala could hardly be coming at a worse moment for Hillary Clinton before she launches her all-but-certain presidential campaign. The presumptive Democratic presidential frontrunner is set to attend the Wednesday night fundraising event amid controversies about her use of a personal email address as secretary of state and the foundation’s own fundraising practices and oversight. Clinton did not address either matter in a widely anticipated speech in Washington on Tuesday night. And as the foundation’s high-profile...