This CL removes the last method taking a raw callback as argument.

Bug: chromium:782550
Change-Id: Ia7f19120be7dcb2648f11cd3cdb8880f8818490d
Reviewed-on: https://chromium-review.googlesource.com/822198
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51695}