Refactor VerifyCertificateChain test data to include a key purpose

net/data/verify_certificate_chain_unittest/rebase-errors.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.
 
 """Helper script to update the test error expectations based on actual results.
 
 This is useful for regenerating test expectations after making changes to the
 error format.
 
@@ skipping 15 matching lines @@
 import os
 import sys
 import re
 
 
 # Regular expression to find the failed errors in test stdout.
 #  * Group 1 of the match is the actual error text (backslash-escaped)
 #  * Group 2 of the match is file path (relative to //src) where the expected
 #    errors were read from.
 failed_test_regex = re.compile(r"""
-Value of: errors.ToDebugString\((?:chain)?\)
+Value of: errors.ToDebugString\((?:test.chain)?\)
   Actual: "(.*)"
 (?:.|\n)+?
 Test file: (.*)
 """, re.MULTILINE)
 
 
 # Regular expression to find the ERRORS block (and any text above it) in a PEM
 # file. The assumption is that ERRORS is not the very first block in the file
 # (since it looks for an -----END to precede it).
 #  * Group 1 of the match is the ERRORS block content and any comments
@@ skipping 121 matching lines @@
 
   for m in failed_test_regex.finditer(test_stdout):
     actual_errors = m.group(1)
     actual_errors = actual_errors.decode('string-escape')
     relative_test_path = m.group(2)
     fixup_errors_for_file(actual_errors, get_abs_path(relative_test_path))
 
 
 if __name__ == "__main__":
   main()