simplify flag handling add _checklink var to dirstate introduce dirstate.flagfunc switch users of util.execfunc/linkfunc to flagfunc change manifestdict.set to take a flags string change ctx.fileflags to ctx.flags change gitmode func to a dict remove util.execfunc/linkfunc [ original upstream description]

use repo.changectx(None) to get a workingctx [ original upstream description]