[Telemetry refactor] Drop "2" from method calls to JS API

tools/perf/metrics/loading.py

 # Copyright 2013 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.value import scalar
 
 from metrics import Metric
 
 
 class LoadingMetric(Metric):
 
   """A metric for page loading time based entirely on window.performance"""
 
   def Start(self, page, tab):
     raise NotImplementedError()
 
   def Stop(self, page, tab):
     raise NotImplementedError()
 
   def AddResults(self, tab, results):
-    load_timings = tab.EvaluateJavaScript2('window.performance.timing')
+    load_timings = tab.EvaluateJavaScript('window.performance.timing')
 
     # NavigationStart relative markers in milliseconds.
     load_start = (
         float(load_timings['loadEventStart']) - load_timings['navigationStart'])
     results.AddValue(scalar.ScalarValue(
         results.current_page, 'load_start', 'ms', load_start))
 
     dom_content_loaded_start = (
         float(load_timings['domContentLoadedEventStart']) -
         load_timings['navigationStart'])
@@ skipping 31 matching lines @@
         float(load_timings['responseStart']) - load_timings['requestStart'])
     results.AddValue(scalar.ScalarValue(
         results.current_page, 'request_duration', 'ms', request_duration,
         important=False))
 
     response_duration = (
         float(load_timings['responseEnd']) - load_timings['responseStart'])
     results.AddValue(scalar.ScalarValue(
         results.current_page, 'response_duration', 'ms', response_duration,
         important=False))