[Telemetry] Cleanup some unused variables in page_sets.

tools/perf/page_sets/service_worker_micro_benchmark.py

 # Copyright 2014 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.
 
 from telemetry.page import page as page
 from telemetry import story
 
 
-archive_data_file_path = 'data/service_worker_micro_benchmark.json'
-
-
 class ServiceWorkerBenchmarkPage(page.Page):
   """Page for workload to measure some specific functions in JS"""
 
   def RunNavigateSteps(self, action_runner):
     super(ServiceWorkerBenchmarkPage, self).RunNavigateSteps(action_runner)
     action_runner.WaitForJavaScriptCondition('window.done')
 
 
 class ServiceWorkerMicroBenchmarkPageSet(story.StorySet):
   """Page set for micro benchmarking of each functions with ServiceWorker"""
 
   def __init__(self):
     super(ServiceWorkerMicroBenchmarkPageSet, self).__init__(
-        archive_data_file=archive_data_file_path,
+        archive_data_file='data/service_worker_micro_benchmark.json',
         cloud_storage_bucket=story.PUBLIC_BUCKET)
 
     # pylint: disable=line-too-long
     # The latest code of localhost:8091 is from:
     # https://github.com/horo-t/Service-Worker-Performance/tree/fix-flakyness
     # (rev: 0cc35c2398526665399ca99fe53147ff81101408)
     # TODO(falken): House the code in GoogleChrome's GitHub repository.
     # pylint: enable=C0301
     # Why: to measure performance of many concurrent fetches
     self.AddStory(ServiceWorkerBenchmarkPage(
         'http://localhost:8091/index.html', self,
         make_javascript_deterministic=False))