Update record_per_area to use results.AddValue(...).

tools/perf/measurements/record_per_area.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.
 
 import time
 
 from measurements import smoothness
 from telemetry.page import page_measurement
+from telemetry.value import scalar
+
 
 class RecordPerArea(page_measurement.PageMeasurement):
   def __init__(self):
     super(RecordPerArea, self).__init__('', True)
 
   def AddCommandLineArgs(self, parser):
     parser.add_option('--start-wait-time', type='float',
                       default=2,
                       help='Wait time before the benchmark is started '
                       '(must be long enought to load all content)')
@@ skipping 31 matching lines @@
 
     tab.WaitForJavaScriptExpression('window.benchmark_results.done', 300)
 
     all_data = tab.EvaluateJavaScript('window.benchmark_results.results')
     for data in all_data:
       width = data['width']
       height = data['height']
       area = width * height
       time_ms = data['time_ms']
 
-      results.Add('area_%07d_%dx%d' % (area, width, height), 'ms', time_ms)
-
+      results.AddValue(scalar.ScalarValue(
+          results.current_page, 'area_%07d_%dx%d' % (area, width, height),
+          'ms', time_ms))