GitLab

https://chromium.googlesource.com/external/leveldb.git/+log/7b945f200339..73d5834eceee

This CL also removes port_chromium's InitOnce implementation, because it
is no longer used by leveldb.

$ git log 7b945f200..73d5834ec --date=short --no-merges --format='%ad %ae %s'
2018-09-11 costan Rework threading in env_posix.cc.
2018-09-10 costan Remove InitOnce from the port API.
2018-09-05 costan Clean up PosixWritableFile in env_posix.cc.

Created with:
  roll-dep src/third_party/leveldatabase/src

Change-Id: Icba857ff32949a1b6f4cd385330a01c7ac02798d
Reviewed-on: https://chromium-review.googlesource.com/c/1220056Reviewed-by: Chris Mumford <cmumford@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596422}