chromeos: Make owner settings code not use blocking pool.

Update OwnerSettingsServiceChromeOS to call
base::CreateTaskRunnerWithTraits() instead of
content::BrowserThread::GetBlockingPool().

BUG=667892

Change-Id: I0e5d037e4081cf9ce79c908790eab20abd20c865
Reviewed-on: https://chromium-review.googlesource.com/560781
Reviewed-by: Mattias Nissler <mnissler@chromium.org>
Commit-Queue: Dan Erat <derat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#484589}
1 file changed