NEW YORK — Chelsea Brown, a dancer and actress who brightened “Rowan & Martin’s Laugh-In” and later found success performing in Australia, has died. Her death Wednesday in Chicago was confirmed by George Schlatter, an executive producer of the zany NBC comedy-sketch series. Her age was reported as 69. During 1968-69 Brown was a member of the “Laugh-In” troupe whose ranks through six seasons also included Goldie Hawn and Lily Tomlin.