GitLab

As part of moving spell check settings to OS settings in Chrome OS,
updating spelling service pref when spell check pref changed is
identified to be better dealt with in spellcheck_service.

Related CL: https://crrev.com/c/2360093

Bug: 1113439
Change-Id: I0532d28d92912e5437ef729bd84b4916ffc55af8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2387912Reviewed-by: Rouslan Solomakhin <rouslan@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: My Nguyen <myy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804535}