The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2983181ccb26aa8a59b8689e20b304fb60c05c3b

commit 2983181ccb26aa8a59b8689e20b304fb60c05c3b
Author: Gabriel Charette <gab@chromium.org>
Date: Wed Mar 28 17:01:09 2018

Migrate BrowserThread::IsMessageLoopValid to BrowserThread::IsThreadInitialized.

The two methods converged over the last year and are now equivalent.

Bug: 825054
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I4ec5f7afb5b7b21278af6c777efe9ad57d2aae68
Reviewed-on: https://chromium-review.googlesource.com/977063
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546529}
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/chromeos/boot_times_recorder.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/media/webrtc/media_stream_capture_indicator.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/metrics/chrome_metrics_service_accessor.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/predictors/predictor_database.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/process_singleton_posix.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/profiles/profile_io_data.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/sync_file_system/local/sync_file_system_backend.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/chrome/browser/task_manager/sampling/task_manager_io_thread_helper.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/appcache/chrome_appcache_service.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/blob_storage/chrome_blob_storage_context.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/browser_context.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/browser_thread_impl.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/host_zoom_level_context.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/renderer_host/media/media_stream_manager.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/storage_partition_impl.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/storage_partition_impl_map.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/browser/streams/stream_context.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/public/browser/browser_thread.h
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/content/public/test/test_utils.cc
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/extensions/browser/api/api_resource_manager.h
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/ios/chrome/browser/browser_state/chrome_browser_state_io_data.mm
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/ios/components/io_thread/ios_io_thread.mm
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/ios/web/public/web_thread.h
[modify] https://crrev.com/2983181ccb26aa8a59b8689e20b304fb60c05c3b/ios/web/web_thread_impl.cc