[build] Deprecate using gold plugin

https://codereview.chromium.org/2957523002 deprecated using the gold
plugin on the chromium side.

TBR=mstarzinger@chromium.org
NOTRY=true

Bug: v8:6524
Change-Id: Id82ac677c9c858725cc89ec7a87a8917fb29a451
Reviewed-on: https://chromium-review.googlesource.com/547058Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46198}

DEPS

@@ -269,12 +269,6 @@ hooks = [
     'pattern': '.',
     'action': ['python', 'v8/tools/clang/scripts/update.py', '--if-needed'],
   },
-  {
-    # Pull gold plugin if needed or requested via GYP_DEFINES.
-    'name': 'gold_plugin',
-    'pattern': '.',
-    'action': ['python', 'v8/gypfiles/download_gold_plugin.py'],
-  },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",

gypfiles/download_gold_plugin.py

-#!/usr/bin/env python
-# Copyright 2015 the V8 project authors. All rights reserved.
-# Copyright 2015 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.
-
-"""Script to download LLVM gold plugin from google storage."""
-
-import json
-import os
-import re
-import platform
-import shutil
-import subprocess
-import sys
-import zipfile
-
-# Bail out on windows and cygwin.
-if "win" in platform.system().lower():
-  # Python 2.7.6 hangs at the second path.insert command on windows. Works
-  # with python 2.7.8.
-  print "Gold plugin download not supported on windows."
-  sys.exit(0)
-
-SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
-CHROME_SRC = os.path.abspath(os.path.join(SCRIPT_DIR, os.pardir))
-sys.path.insert(0, os.path.join(CHROME_SRC, 'tools'))
-
-import find_depot_tools
-
-DEPOT_PATH = find_depot_tools.add_depot_tools_to_path()
-GSUTIL_PATH = os.path.join(DEPOT_PATH, 'gsutil.py')
-
-LLVM_BUILD_PATH = os.path.join(CHROME_SRC, 'third_party', 'llvm-build',
-                               'Release+Asserts')
-CLANG_UPDATE_PY = os.path.join(CHROME_SRC, 'tools', 'clang', 'scripts',
-                               'update.py')
-CLANG_REVISION = os.popen(CLANG_UPDATE_PY + ' --print-revision').read().rstrip()
-
-CLANG_BUCKET = 'gs://chromium-browser-clang/Linux_x64'
-
-GOLD_PLUGIN_PATH = os.path.join(LLVM_BUILD_PATH, 'lib', 'LLVMgold.so')
-
-GOLD_PLUGIN_VERSION_FILE = os.path.join(CHROME_SRC, 'gypfiles', '.gold_plugin')
-
-def main():
-  if not re.search(r'cfi_vptr=1', os.environ.get('GYP_DEFINES', '')):
-    # Bailout if this is not a cfi build.
-    print 'Skipping gold plugin download for non-cfi build.'
-    return 0
-  previous_version = ''
-  if os.path.exists(GOLD_PLUGIN_VERSION_FILE):
-    with open(GOLD_PLUGIN_VERSION_FILE) as f:
-      previous_version = f.read().strip()
-  if (os.path.exists(GOLD_PLUGIN_PATH) and previous_version == CLANG_REVISION):
-    # Bailout if gold plugin is up-to-date. This requires the script to be run
-    # after the clang update step.
-    print 'Skipping gold plugin download (up to date).'
-    return 0
-
-  # Make sure clang has been downloaded already.
-  assert os.path.exists(LLVM_BUILD_PATH)
-
-  targz_name = 'llvmgold-%s.tgz' % CLANG_REVISION
-  remote_path = '%s/%s' % (CLANG_BUCKET, targz_name)
-
-  os.chdir(LLVM_BUILD_PATH)
-
-  # TODO(pcc): Fix gsutil.py cp url file < /dev/null 2>&0
-  # (currently aborts with exit code 1,
-  # https://github.com/GoogleCloudPlatform/gsutil/issues/289) or change the
-  # stdin->stderr redirect in update.py to do something else (crbug.com/494442).
-  subprocess.check_call(['python', GSUTIL_PATH,
-                         'cp', remote_path, targz_name],
-                        stderr=open('/dev/null', 'w'))
-  subprocess.check_call(['tar', 'xzf', targz_name])
-  os.remove(targz_name)
-
-  with open(GOLD_PLUGIN_VERSION_FILE, 'w') as f:
-    f.write(CLANG_REVISION)
-  return 0
-
-if __name__ == '__main__':
-  sys.exit(main())