L.A. schools Supt. John Deasy is expected to announce Tuesday night that the nation’s second-largest school system will no longer offer chocolate- and strawberry-flavored milk starting next fall. The announcement, according to district and entertainment-industry sources, will be made on “Jimmy Kimmel Live!” during an appearance with celebrity chef Jamie Oliver. The policy change is part of a carefully negotiated happy ending between the Los Angeles Unified School District and Oliver. The chef has made his confrontations with the school system a main theme of the current season of his reality show, “Jamie Oliver’s Food Revolution.” Both Oliver’s and Kimmel’s shows air on ABC.