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

tools/perf/page_sets/image_decoding_measurement.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_module
 from telemetry import story
 
 
 class ImageDecodingMeasurementPage(page_module.Page):
 
   def __init__(self, url, page_set):
     super(ImageDecodingMeasurementPage, self).__init__(url=url,
                                                        page_set=page_set)
     self.image_decoding_measurement_limit_results_to_min_iterations = True
 
   def RunNavigateSteps(self, action_runner):
     super(ImageDecodingMeasurementPage, self).RunNavigateSteps(action_runner)
-    action_runner.ExecuteJavaScript2('runBenchmark();')
-    action_runner.WaitForJavaScriptCondition2('isDone')
+    action_runner.ExecuteJavaScript('runBenchmark();')
+    action_runner.WaitForJavaScriptCondition('isDone')
 
 
 class ImageDecodingMeasurementPageSet(story.StorySet):
 
   """ A directed benchmark of image decoding performance """
 
   def __init__(self):
     super(ImageDecodingMeasurementPageSet, self).__init__()
     self.image_decoding_measurement_limit_results_to_min_iterations = True
 
     urls_list = [
       'file://../../../chrome/test/data/image_decoding/image_decoding.html?gif',
       'file://../../../chrome/test/data/image_decoding/image_decoding.html?jpg',
       'file://../../../chrome/test/data/image_decoding/image_decoding.html?png',
       'file://../../../chrome/test/data/image_decoding/image_decoding.html?webp'
     ]
 
     for url in urls_list:
       self.AddStory(ImageDecodingMeasurementPage(url, self))