Add a helper script to do abseil rolls

Bug: None
Change-Id: I4b98e28ada4343a8674d4755dd9b8b224402b5b2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2289778
Commit-Queue: Danil Chapovalov <danilchap@chromium.org>
Reviewed-by: Mirko Bonadei <mbonadei@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797236}

third_party/abseil-cpp/patches/0002-delete-unprefixed-annotations.patch

+diff --git a/third_party/abseil-cpp/absl/base/dynamic_annotations.h b/third_party/abseil-cpp/absl/base/dynamic_annotations.h
+index 1444dc48e283..6687291cade3 100644
+--- a/third_party/abseil-cpp/absl/base/dynamic_annotations.h
++++ b/third_party/abseil-cpp/absl/base/dynamic_annotations.h
+@@ -49,9 +49,6 @@
+ 
+ #include "absl/base/config.h"
+ 
+-// TODO(rogeeff): Remove after the backward compatibility period.
+-#include "absl/base/internal/dynamic_annotations.h"  // IWYU pragma: export
+-
+ // -------------------------------------------------------------------------
+ // Decide which features are enabled
+ 
+diff --git a/third_party/abseil-cpp/absl/base/thread_annotations.h b/third_party/abseil-cpp/absl/base/thread_annotations.h
+index 5f51c0c2d2d5..10b9bde551a7 100644
+--- a/third_party/abseil-cpp/absl/base/thread_annotations.h
++++ b/third_party/abseil-cpp/absl/base/thread_annotations.h
+@@ -35,8 +35,6 @@
+ #define ABSL_BASE_THREAD_ANNOTATIONS_H_
+ 
+ #include "absl/base/config.h"
+-// TODO(mbonadei): Remove after the backward compatibility period.
+-#include "absl/base/internal/thread_annotations.h"  // IWYU pragma: export
+ 
+ #if defined(__clang__)
+ #define ABSL_INTERNAL_THREAD_ANNOTATION_ATTRIBUTE(x) __attribute__((x))

third_party/abseil-cpp/roll_abseil.py

+#!/usr/bin/env python
+
+# NOTE: This script requires python 3.
+
+"""Script to do the first step of Abseil roll into chromium.
+"""
+
+import logging
+import os
+import re
+import subprocess
+import tempfile
+from datetime import datetime
+
+ABSL_URI = 'https://github.com/abseil/abseil-cpp.git'
+
+def _PullAbseil(abseil_dir):
+  logging.info('Updating abseil...')
+  subprocess.check_call(['git', 'clone', ABSL_URI],
+                        cwd=abseil_dir)
+
+def _SyncChromium(chromium_dir):
+  logging.info('Updating chromium...')
+  subprocess.check_call(['git', 'checkout', 'master'], cwd=chromium_dir)
+  subprocess.check_call(['git', 'pull', '--rebase'], cwd=chromium_dir)
+  subprocess.check_call(['gclient', 'sync'], cwd=chromium_dir)
+
+
+def _UpdateChromiumReadme(readme_filename, abseil_dir):
+  logging.info('Updating ' + readme_filename)
+
+  stdout = subprocess.check_output(['git', 'log', '-n1', '--pretty=short'],
+                                   cwd=abseil_dir)
+  new_revision = re.search('commit\\s(.{40})', str(stdout)).group(1)
+
+  with open(readme_filename, 'r+') as f:
+    content = f.read()
+    prefix = 'Revision: '
+    pos = content.find(prefix)
+    assert(pos > 0)
+    pos = pos + len(prefix)
+    old_revision = content[pos:pos+40]
+    f.seek(pos)
+    f.write(new_revision)
+
+  logging.info('Abseil old revision is ' + old_revision)
+  logging.info('Abseil new revision is ' + new_revision)
+  return old_revision[0:10] + '..' + new_revision[0:10]
+
+
+def _UpdateAbseilInChromium(abseil_dir, chromium_dir):
+ logging.info('Syncing abseil in chromium/src/third_party...')
+ exclude = [
+   '*BUILD.gn',
+   'README.chromium',
+   'OWNERS',
+   '.gitignore',
+   '.git',
+   '*.gni',
+   '*clang-format',
+   'patches/*',
+   'patches',
+   'absl_hardening_test.cc',
+   'roll_abseil.py',
+   'generate_def_files.py',
+   '*.def',
+ ]
+ params = ['rsync', '-aP', abseil_dir, os.path.join(chromium_dir, 'third_party'), '--delete']
+ for e in exclude:
+   params.append('--exclude={}'.format(e))
+ subprocess.check_call(params, cwd=chromium_dir)
+
+
+def _PatchAbseil(abseil_in_chromium_dir):
+  logging.info('Patching abseil...')
+  for patch in os.listdir(os.path.join(abseil_in_chromium_dir, 'patches')):
+    subprocess.check_call(['patch', '--strip', '1', '-i', os.path.join(abseil_in_chromium_dir, 'patches', patch)])
+
+  os.remove(os.path.join(abseil_in_chromium_dir, 'absl', 'base', 'internal', 'thread_annotations.h'))
+  os.remove(os.path.join(abseil_in_chromium_dir, 'absl', 'base', 'internal', 'dynamic_annotations.h'))
+  #Chromium complains when a script file doesn't have execute permission.
+  os.chmod(os.path.join(abseil_in_chromium_dir, 'conanfile.py'), 0o750)
+
+
+def _Commit(chromium_dir, hash_diff):
+  logging.info('Commit...')
+  desc="""Roll abseil_revision {0}
+
+Change Log:
+https://chromium.googlesource.com/external/github.com/abseil/abseil-cpp/+log/{0}
+Full diff:
+https://chromium.googlesource.com/external/github.com/abseil/abseil-cpp/+/{0}
+Bug: None""".format(hash_diff)
+
+  subprocess.check_call(['git', 'add', 'third_party/abseil-cpp'], cwd=chromium_dir)
+  subprocess.check_call(['git', 'commit', '-m', desc], cwd=chromium_dir)
+
+  logging.info('Upload...')
+  subprocess.check_call(['git', 'cl', 'upload', '-m', desc, '--bypass-hooks'], cwd=chromium_dir)
+
+
+def _Roll():
+  chromium_dir = os.getcwd()
+  abseil_in_chromium_dir = os.path.join(chromium_dir, 'third_party', 'abseil-cpp')
+  _SyncChromium(chromium_dir)
+
+  branch_name = datetime.today().strftime('rolling-absl-%Y%m%d')
+  logging.info('Creating branch ' + branch_name + ' for the roll...')
+  subprocess.check_call(['git', 'checkout', '-b', branch_name], cwd=chromium_dir)
+
+  with tempfile.TemporaryDirectory() as abseil_root:
+    _PullAbseil(abseil_root)
+    abseil_dir = os.path.join(abseil_root, 'abseil-cpp')
+    _UpdateAbseilInChromium(abseil_dir, chromium_dir)
+    hash_diff = _UpdateChromiumReadme(os.path.join(abseil_in_chromium_dir, 'README.chromium'),
+                                      abseil_dir)
+
+  _PatchAbseil(abseil_in_chromium_dir)
+  _Commit(chromium_dir, hash_diff)
+
+
+if __name__ == '__main__':
+  logging.getLogger().setLevel(logging.INFO)
+
+  if os.getcwd().endswith('src') and os.path.exists('chrome/browser'):
+    _Roll()
+
+    logging.info("Next step is manual: Fix BUILD.gn files to match BUILD.bazel changes.")
+    logging.info("After that run generate_def_files.py. ")
+  else:
+    logging.error('Run this script from a chromium/src/ directory.')
+
+