Add new Telemetry tests to get CPU and memory usage for idle and flinging two test scenarios. Mirro…

chrome/test/media_router/telemetry/benchmarks/media_router_metric.py

-# Copyright 2016 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
-
-from telemetry.value import histogram
-from telemetry.value import histogram_util
-from telemetry.value import scalar
-
-from metrics import Metric
-
-HISTOGRAMS_TO_RECORD = [
-  {
-      'name': 'MediaRouter.Ui.Dialog.LoadedWithData', 'units': 'ms',
-      'display_name': 'dialog_loaded_with_data',
-      'type': histogram_util.BROWSER_HISTOGRAM,
-      'description': 'The latency to render the media router dialog with data.',
-  },
-  {
-      'name': 'MediaRouter.Ui.Dialog.Paint', 'units': 'ms',
-      'display_name': 'dialog_paint',
-      'type': histogram_util.BROWSER_HISTOGRAM,
-      'description': 'The latency to paint the media router dialog.',
-  }]
-
-
-class MediaRouterMetric(Metric):
-  "A metric for media router dialog latency from histograms."
-
-  def __init__(self):
-    super(MediaRouterMetric, self).__init__()
-    self._histogram_start = dict()
-    self._histogram_delta = dict()
-    self._started = False
-
-  def Start(self, page, tab):
-    self._started = True
-
-    for h in HISTOGRAMS_TO_RECORD:
-      histogram_data = histogram_util.GetHistogram(
-          h['type'], h['name'], tab)
-      # Histogram data may not be available
-      if not histogram_data:
-        continue
-      self._histogram_start[h['name']] = histogram_data
-
-  def Stop(self, page, tab):
-    assert self._started, 'Must call Start() first'
-    for h in HISTOGRAMS_TO_RECORD:
-      # Histogram data may not be available
-      if h['name'] not in self._histogram_start:
-        continue
-      histogram_data = histogram_util.GetHistogram(
-          h['type'], h['name'], tab)
-
-      if not histogram_data:
-        continue
-      self._histogram_delta[h['name']] = histogram_util.SubtractHistogram(
-          histogram_data, self._histogram_start[h['name']])
-
-  def AddResults(self, tab, results):
-    assert self._histogram_delta, 'Must call Stop() first'
-    for h in HISTOGRAMS_TO_RECORD:
-      # Histogram data may not be available
-      if h['name'] not in self._histogram_delta:
-        continue
-      results.AddValue(histogram.HistogramValue(
-          results.current_page, h['display_name'], h['units'],
-          raw_value_json=self._histogram_delta[h['name']], important=False,
-          description=h.get('description')))