Refactor how net/data/verify_certificate_chain_unittest/*

net/data/verify_certificate_chain_unittest/expired-unconstrained-root/generate-chains.py

 #!/usr/bin/python
 # Copyright (c) 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Certificate chain with 1 intermediate, where the root certificate is expired
 (violates validity.notAfter). Verification is expected to succeed as
 the trust anchor has no constraints (so expiration of the certificate is not
 enforced)."""
 
+import sys
+sys.path += ['..']
+
 import common
 
 # Self-signed root certificate (used as trust anchor).
 root = common.create_self_signed_root_certificate('Root')
 root.set_validity_range(common.JANUARY_1_2015_UTC, common.MARCH_1_2015_UTC)
 
 # Intermediate certificate.
 intermediate = common.create_intermediate_certificate('Intermediate', root)
 intermediate.set_validity_range(common.JANUARY_1_2015_UTC,
                                 common.JANUARY_1_2016_UTC)
 
 # Target certificate.
 target = common.create_end_entity_certificate('Target', intermediate)
 target.set_validity_range(common.JANUARY_1_2015_UTC, common.JANUARY_1_2016_UTC)
 
-chain = [target, intermediate]
-trusted = common.TrustAnchor(root, constrained=False)
 
 # Both the target and intermediate are valid at this time, however the
 # root is not. This doesn't matter since the root certificate is
 # just a delivery mechanism for the name + SPKI.
-time = common.MARCH_2_2015_UTC
-key_purpose = common.DEFAULT_KEY_PURPOSE
-verify_result = True
-errors = None
 
-common.write_test_file(__doc__, chain, trusted, time, key_purpose,
-                       verify_result, errors)
+chain = [target, intermediate, root]
+common.write_chain(__doc__, chain, 'chain.pem')