[telemetry] Make single-benchmark measurements protected and undiscoverable.

tools/perf/benchmarks/dom_perf.py

 # Copyright (c) 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 json
 import math
 import os
 
 from telemetry import test
 from telemetry.core import util
@@ skipping 17 matching lines @@
   # Raise e to that sum over the number of values.
   mean = math.pow(math.e, (log_sum / len(new_values)))
   # Return the rounded mean.
   return int(round(mean))
 
 
 SCORE_UNIT = 'score (bigger is better)'
 SCORE_TRACE_NAME = 'score'
 
 
-class DomPerfMeasurement(page_measurement.PageMeasurement):
+class _DomPerfMeasurement(page_measurement.PageMeasurement):
   @property
   def results_are_the_same_on_every_page(self):
     return False
 
   def MeasurePage(self, page, tab, results):
     try:
       def _IsDone():
         return tab.GetCookieByName('__domperf_finished') == '1'
       util.WaitFor(_IsDone, 600)
 
@@ skipping 14 matching lines @@
     total = _GeometricMean(scores)
     results.AddSummary(SCORE_TRACE_NAME, SCORE_UNIT, total, 'Total')
 
 
 class DomPerf(test.Test):
   """A suite of JavaScript benchmarks for exercising the browser's DOM.
 
   The final score is computed as the geometric mean of the individual results.
   Scores are not comparable across benchmark suite versions and higher scores
   means better performance: Bigger is better!"""
-  test = DomPerfMeasurement
+  test = _DomPerfMeasurement
 
   def CreatePageSet(self, options):
     dom_perf_dir = os.path.join(util.GetChromiumSrcDir(), 'data', 'dom_perf')
     base_page = 'file://run.html?reportInJS=1&run='
     return page_set.PageSet.FromDict({
         'pages': [
           { 'url': base_page + 'Accessors' },
           { 'url': base_page + 'CloneNodes' },
           { 'url': base_page + 'CreateNodes' },
           { 'url': base_page + 'DOMDivWalk' },
           { 'url': base_page + 'DOMTable' },
           { 'url': base_page + 'DOMWalk' },
           { 'url': base_page + 'Events' },
           { 'url': base_page + 'Get+Elements' },
           { 'url': base_page + 'GridSort' },
           { 'url': base_page + 'Template' }
           ]
         }, dom_perf_dir)