narrow: add trailing slash to dir earlier for debug{revlog,index,data} The treemanifest code internally uses trailing slashes on directories (except for the root directory, which is an empty string). We should make sure we pass in directories with trailing slashes when we work with the treemanifest code. For some reason, I seem to have decided to be nice to the callers instead in 49c583ca48c4 (treemanifest: add --dir option to debug{revlog,data,index}, 2015-04-12). Let's fix that and pay the cost of fixing up the directory name close close to where we get it from the user. Differential Revision: https://phab.mercurial-scm.org/D3032