Merging 3 commit(s) from Chromium's toolchain-utils

Doing this for 8acdba6, which introduces the script that generated
this commit.

Merged commit digest:
  c968b02 afdo_metadata: Publish new profiles for Chrome.
  8acdba6 Add a merge-with-upstream script to toolchain-utils
  f723413 toolchain-utils: update skylab credential location for role account

Change-Id: I64dc02294d6a2b645c70198ebee680c356b94387