This patch causes a compile failure, probably because some symbols had
been declared in the root namespace and should have been moved to base.
(but weren't compiled under Linux)

BUG=

This reverts commit f41e04db.

Change-Id: Ia2292bf9dcbf429f47c8c8632356574a91ff0a1d
Reviewed-on: https://chromium-review.googlesource.com/295110Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>