Telemetry media_measurement plus play action and tests.

tools/perf/perf_tools/media_measurement.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.
+
+"""Media measurement class gathers media related metrics on a page set.
+
+Media metrics recorded are controlled by media_metrics.js.  At the end of the
+test each metrics for every media element in the page are reported.
+"""
+from perf_tools import  media_metrics
+
+from telemetry.page import page_measurement
+
+
+class MediaMeasurement(page_measurement.PageMeasurement):
+  """Provide general video and audio metrics."""
+
+  def __init__(self):
+    super(MediaMeasurement, self).__init__('media_metrics')
+    self.metrics = None
+
+  def results_are_the_same_on_every_page(self):
+    """Results can vary from page to page based on media events taking place."""
+    return False
+
+  def DidNavigateToPage(self, page, tab):
+    """Override to do operations right after the page is navigated."""
+    self.metrics = media_metrics.MediaMetrics(tab)
+    self.metrics.Start()
+
+  def MeasurePage(self, page, tab, results):
+    """Measure the page's performance."""
+    self.metrics.StopAndGetResults(results)