[iOS] Add the handling of group closing in grid

The aim of this CL is to handle group closing using list change
notification, and  update the `GridViewControllerMutator` closing
function to handle groups and tabs at the same time.

Bug: 1501837
Change-Id: Ia2cd9e7a73913009d313286b5baa38b5510941c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5398199


Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Commit-Queue: Elmehdi Rahmaoui <erahmaoui@google.com>
Cr-Commit-Position: refs/heads/main@{#1280242}