GitLab

This change is made because all subdirectories of ios/web/public
represent features, while web_state subdirectory is class name.

The move proposal was discussed here:
https://docs.google.com/document/d/1C2YIU0rDbH5wz2VI6nk0COrktwY3DbF-e7QbMIAKEJc/edit

TBR=blundel@chromium.org

Bug: 942244
Change-Id: I5227e9a413401e5a599d0d5cbd4758d3eb00aa38
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1793356Reviewed-by: Yi Su <mrsuyi@chromium.org>
Commit-Queue: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695224}