[ADD relevant info inline]

Link to build or pfq page.
https://cros-goldeneye.corp.google.com/chromeos/healthmonitoring/buildDetails?id=2616569

More specifically:
https://logs.chromium.org/v/?s=chromeos%2Fbb%2Fchromeos%2Fwizpig-paladin%2F3215%2F%2B%2Frecipes%2Fsteps%2FBuildPackages%2F0%2Fstdout
https://luci-logdog.appspot.com/v/?s=chromeos/bb/chromeos/fizz-paladin/4250/+/recipes/steps/BuildPackages/0/stdout

build # for that buildbot.
18735

Snippet of log that contains the failure.
Pending 0/593, [Time 15:32:45 | Elapsed 60m22.0s | Load 1.67 5.91 21.58]
Merge complete
Done
Builds complete
INFO    : fetching the debug symbols
cros_install_debug_syms: Unhandled exception:
Traceback (most recent call last):
  File "/mnt/host/source/chromite/bin/cros_install_debug_syms", line 169, in <module>
    DoMain()
  File "/mnt/host/source/chromite/bin/cros_install_debug_syms", line 165, in DoMain
    commandline.ScriptWrapperMain(FindTarget)
  File "/mnt/host/source/chromite/lib/commandline.py", line 911, in ScriptWrapperMain
    ret = target(argv[1:])
  File "/mnt/host/source/chromite/scripts/cros_install_debug_syms.py", line 323, in main
    processes=options.jobs)
  File "/mnt/host/source/chromite/lib/parallel.py", line 810, in RunTasksInProcessPool
    queue.put((idx, input_args))
  File "/usr/lib64/python2.7/contextlib.py", line 24, in __exit__
    self.gen.next()
  File "/mnt/host/source/chromite/lib/parallel.py", line 751, in BackgroundTaskRunner
    queue.put(_AllTasksComplete())
  File "/mnt/host/source/chromite/lib/parallel.py", line 751, in BackgroundTaskRunner
    queue.put(_AllTasksComplete())
  File "/usr/lib64/python2.7/contextlib.py", line 24, in __exit__
    self.gen.next()
  File "/mnt/host/source/chromite/lib/parallel.py", line 562, in ParallelTasks
    raise BackgroundFailure(exc_infos=errors)
...
ServiceException: 500 We encountered an internal error. Please try again.
<?xml version='1.0' encoding='UTF-8'?><Error><Code>RpcError</Code><Message>We encountered an internal error. Please try again.</Message></Error>
ServiceException: 503 
CommandException: Some components of /build/fizz/packages/chromeos-base/chromeos-chrome-69.0.3444.0_rc-r1.debug.tbz2 were not downloaded successfully. Please retry this download.
cmd=['/mnt/host/source/.cache/common/gsutil_4.30.tar.gz/gsutil/gsutil', '-o', 'Boto:num_retries=10', 'cp', '-v', '--', 'gs://chromeos-prebuilt/board/caroline/chrome-R69-10731.0.0-rc1/packages/chromeos-base/chromeos-chrome-69.0.3444.0_rc-r1.debug.tbz2', u'/build/fizz/packages/chromeos-base/chromeos-chrome-69.0.3444.0_rc-r1.debug.tbz2'], extra env={'BOTO_CONFIG': u'/mnt/host/source/src/private-overlays/chromeos-overlay/googlestorage_account.boto'}
Traceback (most recent call last):
  File "/mnt/host/source/chromite/lib/parallel.py", line 603, in TaskRunner
    task(*x, **task_kwargs)
  File "/mnt/host/source/chromite/lib/parallel.py", line 801, in <lambda>
    fn = lambda idx, task_args: out_queue.put((idx, task(*task_args)))
  File "/mnt/host/source/chromite/scripts/cros_install_debug_syms.py", line 95, in Install
    self._gs_context.Copy(url, archive, debug_level=logging.DEBUG)
  File "/mnt/host/source/chromite/lib/gs.py", line 1006, in Copy
    raise
  File "/mnt/host/source/chromite/lib/gs.py", line 983, in Copy
    result = self.DoCommand(cmd, **kwargs)
  File "/mnt/host/source/chromite/lib/gs.py", line 919, in DoCommand
    raise GSCommandError(e.msg, e.result, e.exception)
GSCommandError: return code: 1; command: /mnt/host/source/.cache/common/gsutil_4.30.tar.gz/gsutil/gsutil -o 'Boto:num_retries=10' cp -v -- gs://chromeos-prebuilt/board/caroline/chrome-R69-10731.0.0-rc1/packages/chromeos-base/chromeos-chrome-69.0.3444.0_rc-r1.debug.tbz2 /build/fizz/packages/chromeos-base/chromeos-chrome-69.0.3444.0_rc-r1.debug.tbz2