[Telemetry] Add memory and IO stats to page cycler

tools/telemetry/telemetry/core/chrome/platform_backend.py

Index: tools/telemetry/telemetry/core/chrome/platform_backend.py
diff --git a/tools/telemetry/telemetry/core/chrome/platform_backend.py b/tools/telemetry/telemetry/core/chrome/platform_backend.py
new file mode 100644
index 0000000000000000000000000000000000000000..adef92adaa1cf0ccc5bf7a1168964ec3139c1748
--- /dev/null
+++ b/tools/telemetry/telemetry/core/chrome/platform_backend.py
@@ -0,0 +1,38 @@
+# 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.
+
+class PlatformBackend(object):
+  def IsRawDisplayFrameRateSupported(self):
+    return False
+
+  # pylint: disable=W0613
+  def StartRawDisplayFrameRateMeasurement(self, trace_tag):
+    raise NotImplementedError()
+
+  def StopRawDisplayFrameRateMeasurement(self):
+    raise NotImplementedError()
+
+  def SetFullPerformanceModeEnabled(self, enabled):  # pylint: disable=W0613
+    pass
+
+  def CanMonitorThermalThrottling(self):
+    return False
+
+  def IsThermallyThrottled(self):
+    raise NotImplementedError()
+
+  def HasBeenThermallyThrottled(self):
+    raise NotImplementedError()
+
+  def GetSystemCommitCharge(self):
+    raise NotImplementedError()
+
+  def GetMemoryStats(self, pid):  # pylint: disable=W0613
+    return {}
+
+  def GetIOStats(self, pid):  # pylint: disable=W0613
+    return {}
+
+  def GetChildPids(self, pid):  # pylint: disable=W0613
+    raise NotImplementedError()