thermald: remove base::MessageLoop::current()

base::MessageLoop::current() will be deprecated in libchrome r680000.
base::MessageLoop::current()->task_runner() is replaced by equivalent
base::ThreadTaskRunnerHandle::Get().

BUG=chromium:1054279
TEST=unittests

Change-Id: I24381593ad94ffe7f28baf64463e8fc9407cd960
Reviewed-on: https://chrome-internal-review.googlesource.com/c/chromeos/thermald/+/2924039
Tested-by: Grace Cham <hscham@google.com>
Commit-Queue: Qijiang Fan <fqj@google.com>
Reviewed-by: Qijiang Fan <fqj@google.com>
2 files changed