Failing build:
https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?buildbucketId=8936337365466558960

Build log:
https://luci-logdog.appspot.com/v/?s=chromeos/buildbucket/cr-buildbucket.appspot.com/8936337365466558960/+/steps/MasterSlaveSyncCompletion/0/stdout

01:05:00: INFO: Running cidb query on pid 2092, repr(query) starts with <sqlalchemy.sql.expression.Update object at 0x7fc345cbfb50>
Preconditions for the stage successfully met. Beginning to execute stage...
01:05:00: INFO: Running cidb query on pid 2092, repr(query) starts with <sqlalchemy.sql.expression.Update object at 0x7fc345cbfdd0>
01:05:00: INFO: Running cidb query on pid 2092, repr(query) starts with 'SELECT id, build_stage_id, outer_failure_id, exception_type, exception_message, exception_category,
01:05:00: INFO: Running cidb query on pid 2092, repr(query) starts with 'SELECT build_id, build_config, waterfall, builder_name, build_number, message_type, message_subtype
01:05:00: WARNING: The build is not a master.
01:05:00: INFO: The build is not a master.
01:05:00: WARNING: The following builders failed with this manifest:
caroline-chrome-pfq
Please check the logs of the failing builders for details.
01:05:00: WARNING: 
01:05:00: INFO: Running cidb query on pid 2092, repr(query) starts with <sqlalchemy.sql.expression.Update object at 0x7fc345cbf790>


This seems new, maybe it's a transient error.