[telemetry] Disable IPPET power monitor

tools/telemetry/telemetry/core/platform/power_monitor/ippet_power_monitor.py

 # Copyright 2014 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 csv
 import logging
 import operator
 import os
 import platform
 import re
@@ skipping 53 matching lines @@
 
 class IppetPowerMonitor(power_monitor.PowerMonitor):
   def __init__(self, backend):
     super(IppetPowerMonitor, self).__init__()
     self._backend = backend
     self._ippet_handle = None
     self._ippet_port = None
     self._output_dir = None
 
   def CanMonitorPower(self):
+    # IPPET disabled because of flakiness (crbug.com/336558).
+    if True:
+      return False
+
     if not win32event:
       return False
 
     windows_7_or_later = (
         self._backend.GetOSName() == 'win' and
         self._backend.GetOSVersionName() >= platform_backend.WIN7)
     if not windows_7_or_later:
       return False
 
     # This check works on Windows only.
@@ skipping 143 matching lines @@
     # Note that this is only an estimate of Chrome's CPU power usage.
     if chrome_keys:
       per_process_power_usage = [
           get(key, 'CPU Power W', default=0, mult=1000) for key in chrome_keys]
       result['application_energy_consumption_mwh'] = (
           sum(map(operator.mul,
                   map(sum, zip(*per_process_power_usage)),
                   get('sys', 'Interval(secs)', mult=1./3600.))))
 
     return result