Ann Devroy, 49, veteran news reporter who was White House correspondent for the Washington Post. President Clinton, in a statement, praised Devroy for her exceptional "skill, shrewd analysis and gruff grace." Born in Green Bay, Wis., she graduated from the University of Wisconsin and worked in that state and New Jersey before moving to the Washington bureau of the Gannett News Service in 1977. She joined the Post as political editor in 1985 and later transferred to the White House to cover President George Bush and then Clinton. On Thursday in Washington of lung cancer.