Mango Tree, CityCenterDC's glitzy Thai import, has a new chef in charge after four months. Former sous chef Adrian Salazar is taking over for opening-day chef de cuisine Paul Kennedy.Kennedy's cooking helped Mango Tree earn a positive 2.5-star review from The Post's Tom Sietsema in February: "Eating his papaya salad, funky with dried shrimp and pulsing with heat, puts me in mind of Bangkok," Sietsema wrote.