Revert of Update buildbots to parse new telemetry JSON format.

scripts/slave/performance_log_processor.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.
 
 """This module contains PerformanceLogProcessor and subclasses.
 
 Several performance tests have complicated log output, this module is intended
 to help buildsteps parse these logs and identify if tests had anomalies.
 
 The classes in this file all have the same method ProcessLine, just like
@@ skipping 94 matching lines @@
     self._channel = build_properties.get('channel', 'undefined')
     self._webrtc_revision = build_properties.get('got_webrtc_revision',
                                                  'undefined')
 
     self._v8_revision = 'undefined'
     if factory_properties.get('show_v8_revision'):
       self._v8_revision = build_properties.get('got_v8_revision', 'undefined')
 
     self._percentiles = [.1, .25, .5, .75, .90, .95, .99]
 
-  def IsChartJson(self):  # pylint: disable=R0201
-    """This is not the new telemetry --chartjson output format."""
-    return False
-
   def PerformanceLogs(self):
     if not self._finalized:
       self._FinalizeProcessing()
       self._finalized = True
     return self._output
 
   def PerformanceSummary(self):
     """Returns a list of strings about performance changes and other info."""
     if not self._finalized:
       self._FinalizeProcessing()
@@ skipping 710 matching lines @@
   if digits >= 100:
     # Don't append a meaningless '.0' to an integer number.
     digits = int(digits)
   # Exponent is now divisible by 3, between -3 and 6 inclusive: (-3, 0, 3, 6).
   return '%s%s' % (digits, metric_prefixes[exponent])
 
 
 def _JoinWithSpacesAndNewLine(words):
   """Joins a list of words together with spaces."""
   return ' '.join(str(w) for w in words) + '\n'