GitLab

There are some trailing includes, and also some forward declarations
that can be removed.

Drive by CL.

BUG=704136
R=guidou@chromium.org

Change-Id: I2cf0d2e9fcc0e273d759ba870718f87a5359e405
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1704719
Auto-Submit: Antonio Gomes <tonikitoo@igalia.com>
Commit-Queue: Guido Urdaneta <guidou@chromium.org>
Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#678273}