[iOS] Fix: Clear Browsing Data CollectionView UI consistency

- Manager holds a reference to the time range item upon creation and update the item text when notified a change of time range.
- Replace the |timePeriod| property with one that is synced with preferences.

Bug: 944230
Change-Id: Id815963830eb2337ae1dfed931259b3d10de68fe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1532010
Commit-Queue: Huanzhong Huang <huanzhong@chromium.org>
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#643396}
1 file changed