Rename convert_404_to_None -> return_none_on_404.

third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py

 # Copyright (c) 2009, Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 68 matching lines @@
     @memoized
     def fetch_retry_summary_json(self, build):
         """Fetches and returns the text of the archived retry_summary file.
 
         This file is expected to contain the results of retrying layout tests
         with and without a patch in a try job. It includes lists of tests
         that failed only with the patch ("failures"), and tests that failed
         both with and without ("ignored").
         """
         url_base = "%s/%s" % (self.builder_results_url_base(build.builder_name), build.build_number)
-        return NetworkTransaction(convert_404_to_None=True).run(
+        return NetworkTransaction(return_none_on_404=True).run(
             lambda: self._fetch_file(url_base, "retry_summary.json"))
 
     def accumulated_results_url_base(self, builder_name):
         return self.builder_results_url_base(builder_name) + "/results/layout-test-results"
 
     @memoized
     def latest_layout_test_results(self, builder_name):
         return self.fetch_layout_test_results(self.accumulated_results_url_base(builder_name))
 
     @memoized
     def fetch_results(self, build):
         return self.fetch_layout_test_results(self.results_url(build.builder_name, build.build_number))
 
     @memoized
     def fetch_layout_test_results(self, results_url):
         """Returns a LayoutTestResults object for results fetched from a given URL."""
-        results_file = NetworkTransaction(convert_404_to_None=True).run(
+        results_file = NetworkTransaction(return_none_on_404=True).run(
             lambda: self._fetch_file(results_url, "failing_results.json"))
-        revision = NetworkTransaction(convert_404_to_None=True).run(
+        revision = NetworkTransaction(return_none_on_404=True).run(
             lambda: self._fetch_file(results_url, "LAST_CHANGE"))
         if not revision:
             results_file = None
         return LayoutTestResults.results_from_string(results_file, revision)
 
     def _fetch_file(self, url_base, file_name):
         # It seems this can return None if the url redirects and then returns 404.
         # FIXME: This could use Web instead of using urllib2 directly.
         result = urllib2.urlopen("%s/%s" % (url_base, file_name))
         if not result:
             return None
         # urlopen returns a file-like object which sometimes works fine with str()
         # but sometimes is a addinfourl object.  In either case calling read() is correct.
         return result.read()