[tools/perf] Delete unused variable

tools/perf/benchmarks/service_worker.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.
 
 import collections
 import page_sets
 import re
 
 from core import perf_benchmark
 
@@ skipping 131 matching lines @@
     self._speed_index.AddResults(tab, results, chart_prefix)
 
 
 class _ServiceWorkerMicroBenchmarkMeasurement(page_test.PageTest):
   """Record results reported by the JS microbenchmark."""
 
   def __init__(self):
     super(_ServiceWorkerMicroBenchmarkMeasurement, self).__init__()
 
   def ValidateAndMeasurePage(self, page, tab, results):
+    del page  # unused
     tab.WaitForJavaScriptExpression('window.done', 40)
     json = tab.EvaluateJavaScript('window.results || {}')
     for key, value in json.iteritems():
       results.AddValue(scalar.ScalarValue(
           results.current_page, key, value['units'], value['value']))
 
 
 class ServiceWorkerPerfTest(perf_benchmark.PerfBenchmark):
   """Performance test of pages using ServiceWorker.
 
@@ skipping 21 matching lines @@
   page_set = page_sets.ServiceWorkerMicroBenchmarkPageSet
 
   @classmethod
   def Name(cls):
     return 'service_worker.service_worker_micro_benchmark'
 
   @classmethod
   def ShouldDisable(cls, possible_browser):  # http://crbug.com/597656
       return (possible_browser.browser_type == 'reference' and
               possible_browser.platform.GetDeviceTypeName() == 'Nexus 5X')