Generalize rebase-errors.py so it works for other files.

net/cert/internal/test_helpers.h

 // Copyright 2015 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.
 
 #ifndef NET_CERT_INTERNAL_TEST_HELPERS_H_
 #define NET_CERT_INTERNAL_TEST_HELPERS_H_
 
 #include <stddef.h>
 
 #include <ostream>
@@ skipping 58 matching lines @@
 // This is the same as the variant above, however it uses template magic so an
 // mappings array can be passed in directly (and the correct length is
 // inferred).
 template <size_t N>
 ::testing::AssertionResult ReadTestDataFromPemFile(
     const std::string& file_path_ascii,
     const PemBlockMapping(&mappings)[N]) {
   return ReadTestDataFromPemFile(file_path_ascii, mappings, N);
 }
 
-// Reads a test case from |file_name|. Test cases are comprised of a
-// certificate chain, trust anchor, a timestamp to validate at, and the
-// expected result of verification.
-void ReadVerifyCertChainTestFromFile(const std::string& file_name,
+// Reads a test case from |file_path_ascii| (which is relative to //src). Test
+// cases are comprised of a certificate chain, trust anchor, a timestamp to
+// validate at, and the expected result of verification.
+// Generally |file_path_ascii| will start with:
+//   net/data/verify_certificate_chain_unittest/
+void ReadVerifyCertChainTestFromFile(const std::string& file_path_ascii,
                                      ParsedCertificateList* chain,
                                      scoped_refptr<TrustAnchor>* trust_anchor,
                                      der::GeneralizedTime* time,
                                      bool* verify_result,
                                      std::string* expected_errors);
 
 // Reads a data file relative to the src root directory.
-std::string ReadTestFileToString(const std::string& file_name);
+std::string ReadTestFileToString(const std::string& file_path_ascii);
 
 }  // namespace net
 
 #endif  // NET_CERT_INTERNAL_TEST_HELPERS_H_