Revert of Remove usages of Timeline commands in telemetry

tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_timeline_unittest.py

Index: tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_timeline_unittest.py
diff --git a/tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_timeline_unittest.py b/tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_timeline_unittest.py
new file mode 100644
index 0000000000000000000000000000000000000000..f653b9c18fd107b2056d39d1233741ae6ff62a24
--- /dev/null
+++ b/tools/telemetry/telemetry/core/backends/chrome_inspector/inspector_timeline_unittest.py
@@ -0,0 +1,41 @@
+# 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.
+
+from telemetry.core import util
+from telemetry.core.backends.chrome_inspector import inspector_timeline
+from telemetry.unittest_util import tab_test_case
+
+
+class InspectorTimelineTabTest(tab_test_case.TabTestCase):
+  """Test case that opens a browser and creates and then checks an event."""
+
+  def _WaitForAnimationFrame(self):
+    """Wait until the variable window.done is set on the tab."""
+    def _IsDone():
+      return bool(self._tab.EvaluateJavaScript('window.done'))
+    util.WaitFor(_IsDone, 5)
+
+  def testGotTimeline(self):
+    # While the timeline is recording, call window.webkitRequestAnimationFrame.
+    # This will create a FireAnimationEvent, which can be checked below. See:
+    # https://developer.mozilla.org/en/docs/Web/API/window.requestAnimationFrame
+    with inspector_timeline.InspectorTimeline.Recorder(self._tab):
+      self._tab.ExecuteJavaScript(
+          """
+          var done = false;
+          function sleep(ms) {
+            var endTime = (new Date().getTime()) + ms;
+            while ((new Date().getTime()) < endTime);
+          }
+          window.webkitRequestAnimationFrame(function() {
+            sleep(10);
+            window.done = true;
+          });
+          """)
+      self._WaitForAnimationFrame()
+
+    # There should be at least a FireAnimationFrame record with some duration.
+    events = self._tab.timeline_model.GetAllEventsOfName('FireAnimationFrame')
+    self.assertTrue(len(events) > 0)
+    self.assertTrue(events[0].duration > 0)