thermald: libchrome r860220 uprev

* base/bind_helpers.h is deleted after its content being moved to
  base/callback_helpers.h
* base::CallbackListSubscription made stand-alone class

BUG=chromium:1179608
TEST=FEATURES=test emerge-mistral thermald with old and new libchrome

Change-Id: If1f3819b2591783e3e3eb27007ba7ead801d337d
Reviewed-on: https://chrome-internal-review.googlesource.com/c/chromeos/thermald/+/3696362
Tested-by: Grace Cham <[email protected]>
Reviewed-by: Qijiang Fan <[email protected]>
Commit-Queue: Grace Cham <[email protected]>
12 files changed