[s13n] Implement IdentityManager::ForceTriggerOnCookieChange

This CL implements IdentityManager::ForceTriggerOnCookieChange,
which wraps GaiaCookieManagerService::ForceOnCookieChangeProcessing.

It's only for replacement of production code for iOS.

Bug: 926872
Change-Id: Ic4e62c7ad27e41727f5a7e84c87d15fae4b215b8
Reviewed-on: https://chromium-review.googlesource.com/c/1457808
Commit-Queue: Julie Jeongeun Kim <jkim@igalia.com>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#630744}
3 files changed