autoupdate: Set the hash_sha256 in devserver (omaha) response

The new changes in update_engine requires the new hex based sha256 hash sent by
omaha to be checked. But, currently in devserver we only sent base64 ecndoed
sha256. This CL adds hash_sha256 in the package tag of the response by
calculating the hex based sha256 hash of the payload.

TEST=cros flash

Change-Id: I4449d90513db2dcd1424a6693ec7ce172135d689
Commit-Ready: Amin Hassani <>
Tested-by: Amin Hassani <>
Reviewed-by: Xixuan Wu <>
Reviewed-by: Don Garrett <>
(cherry picked from commit 9e2adaebc313a9d73b19519c69fe90f3c58e33d8)
Reviewed-by: Keith Haddow <>
Commit-Queue: Keith Haddow <>
Tested-by: Keith Haddow <>
1 file changed