Upgrade six to 1.17.0 am: e835ec95b0 am: c5e2b601d1

Original change: undetermined

Change-Id: I499586460e8a17f0d8f2b75f4b5af87df6ef2270
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>