canonical XML for repo manifests

Change-Id: Ifd7c31f1b65b3d1e780f6cc9aecf353069208741
Merge commit '0865634753fdbf1bd675e2e66f0c54423a5dd1f4'
more canonicalization

Change-Id: I5b4d6c75f5920f2278d73c0fd72ec5d51f971ca0