Revert of Add a script to merge the PGC files (patchset #6 id:120001 of https://codereview.chromium.org/2575543002/ )

Reason for revert:
Breaks the PGO bots.

Original issue's description:
> Add a script to merge the PGC files.
>
> Workaround for a flakyness in pgomgr.exe where it can run out of address
> space while trying to merge all the PGC files at the same time.
>
> This will also allow to upload the pgd file before running the optimize step.
>
> BUG=674956
>
> Review-Url: https://codereview.chromium.org/2575543002
> Cr-Commit-Position: refs/heads/master@{#448332}
> Committed: 6c18b1e861

TBR=scottmg@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=674956

Review-Url: https://codereview.chromium.org/2680683002
Cr-Original-Commit-Position: refs/heads/master@{#448561}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 6c2f8b4bd17f67d03b3e4d85401a0eaa68597afa

win/merge_pgc_files.py

@@ -1,116 +0,0 @@
-#!/usr/bin/env python
-# Copyright 2017 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.
-
-"""Merge the PGC files generated during the profiling step to the PGD database.
-
-This is required to workaround a flakyness in pgomgr.exe where it can run out
-of address space while trying to merge all the PGC files at the same time.
-"""
-
-import glob
-import json
-import optparse
-import os
-import subprocess
-import sys
-
-
-def find_pgomgr(chrome_checkout_dir, target_cpu):
-  """Find pgomgr.exe."""
-  if target_cpu not in ('x86', 'x64'):
-    raise Exception('target_cpu should be x86 or x64.')
-
-  win_toolchain_json_file = os.path.join(chrome_checkout_dir, 'build',
-      'win_toolchain.json')
-  if not os.path.exists(win_toolchain_json_file):
-    raise Exception('The toolchain JSON file is missing.')
-  with open(win_toolchain_json_file) as temp_f:
-    toolchain_data = json.load(temp_f)
-  if not os.path.isdir(toolchain_data['path']):
-    raise Exception('The toolchain JSON file is invalid.')
-
-  pgomgr_dir = os.path.join(toolchain_data['path'], 'VC', 'bin')
-  if target_cpu == 'x64':
-    pgomgr_dir = os.path.join(pgomgr_dir, 'amd64')
-
-  pgomgr_path = os.path.join(pgomgr_dir, 'pgomgr.exe')
-  if not os.path.exists(pgomgr_path):
-    raise Exception('pgomgr.exe is missing from %s.' % pgomgr_dir)
-
-  return pgomgr_path
-
-
-def main():
-  parser = optparse.OptionParser(usage='%prog [options]')
-  parser.add_option('--checkout-dir', help='The Chrome checkout directory.')
-  parser.add_option('--target-cpu', help='The target\'s bitness.')
-  parser.add_option('--build-dir', help='Chrome build directory.')
-  parser.add_option('--binary-name', help='The binary for which the PGC files '
-                    'should be merged, without extension.')
-  options, _ = parser.parse_args()
-
-  if not options.checkout_dir:
-    parser.error('--checkout-dir is required')
-  if not options.target_cpu:
-    parser.error('--target-cpu is required')
-  if not options.build_dir:
-    parser.error('--build-dir is required')
-  if not options.binary_name:
-    parser.error('--binary-name is required')
-
-  # Starts by finding pgomgr.exe.
-  pgomgr_path = find_pgomgr(options.checkout_dir, options.target_cpu)
-
-  pgc_files = glob.glob(os.path.join(options.build_dir,
-                                     '%s*.pgc' % options.binary_name))
-
-  # Number of PGC files that should be merged in each iterations, merging all
-  # the files one by one is really slow but merging more to 10 at a time doesn't
-  # really seem to impact the total time.
-  #
-  # Number of pgc merged per iteration  |  Time (in min)
-  # 1                                   |  27.2
-  # 10                                  |  12.8
-  # 20                                  |  12.0
-  # 30                                  |  11.5
-  # 40                                  |  11.4
-  # 50                                  |  11.5
-  # 60                                  |  11.6
-  # 70                                  |  11.6
-  # 80                                  |  11.7
-  #
-  # TODO(sebmarchand): Measure the memory usage of pgomgr.exe to see how it get
-  #     affected by the number of pgc files.
-  pgc_per_iter = 20
-
-  def _split_in_chunks(items, chunk_size):
-    """Split |items| in chunks of size |chunk_size|.
-
-    Source: http://stackoverflow.com/a/312464
-    """
-    for i in xrange(0, len(items), chunk_size):
-      yield items[i:i + chunk_size]
-
-  for chunk in _split_in_chunks(pgc_files, pgc_per_iter):
-    merge_command = [
-        pgomgr_path,
-        '/merge'
-    ]
-    for pgc_file in chunk:
-      merge_command.append([
-          os.path.join(options.build_dir, pgc_file)
-      ])
-
-    merge_command.append([
-        os.path.join(options.build_dir, '%s.pgd' % options.binary_name)
-    ])
-    proc = subprocess.Popen(merge_command, stdout=subprocess.PIPE)
-    stdout, _ = proc.communicate()
-    if proc.returncode != 0:
-      raise Exception('Error while trying to merge the PGC files:\n%s' % stdout)
-
-
-if __name__ == '__main__':
-  sys.exit(main())