Remove unnecessary constructor of SyncSetupServiceMock

The PrefService isn't required anymore.

Bug: 884159
Change-Id: I6fabe54fe69e56602d8bbbd6134b8cc8acec9e80
Reviewed-on: https://chromium-review.googlesource.com/c/1333773
Reviewed-by: David Roger <droger@chromium.org>
Commit-Queue: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607650}
2 files changed