am 6e8b268d: Fail the build when using a user tag on a non-legacy module. do not merge

Merge commit '6e8b268dec3cc38151dfd0514621219b79a30fa9' into gingerbread-plus-aosp

* commit '6e8b268dec3cc38151dfd0514621219b79a30fa9':
  Fail the build when using a user tag on a non-legacy module. do not merge