remove ThreadLocalStorage::StaticSlot

in favor of the pattern with
NoDestructor<ThreadLocalStorage::Slot> as discussed on PS1 @
https://chromium-review.googlesource.com/c/chromium/src/+/881017/1

StaticSlot has been subject to a possible initialization race:
CHECK_NE(slot_, kInvalidSlotValue) in StaticSlot::Initialize
could fail if another thread initialized it to kInvalidSlotValue

Change-Id: Iefaa1dde6f85842d20561851a9a26ad5f3a20973
Reviewed-on: https://chromium-review.googlesource.com/881017
Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Miriam Gershenson <mgersh@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Gabriel Charette <gab@chromium.org>
Commit-Queue: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537009}

CrOS-Libchrome-Original-Commit: 88a96c6e1b592b920cd00655b88225334c0c4541
8 files changed
tree: b8ef89f64269a47ac81bebb08ac7ce7ded539408
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/