[telemetry] Catch new Cloud Storage error type.

Now that we support prodaccess authentication, gsutil can spew a different kind of error string. We should catch that and convert it to a CredentialsError.


BUG=340449
TEST=prodaccess --lifetime 1; sleep 1; tools/perf/run_benchmark --browser=list  # Should throw a CredentialsError if you have an android device plugged in.

Review URL: https://codereview.chromium.org/154723002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@249508 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 249508