GitLab

Add a generic isManagedPreference method to PrefServiceBridge, making
use of the prefs.h enums.

Migrate Java usages of prefs::kSearchSuggestEnabled to use the generic
methods as a sample (more to follow).

Bug: 1016957
Change-Id: Ib13181fd9ed6c2e2265b08c141985899bfbabe0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1874719Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Natalie Chouinard <chouinard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708790}