This reverts commit 314e3018.

Reason for revert: On second thought, I don't think we want this.

Original change's description:
> cipd: remove windows-386
> 
> Running depot_tools on Windows 32 bits is not supported anymore.
> 
> Add a comment to cipd_manifest.txt to help people to figure out by themselves
> where to look to do a roll.
> 
> Change-Id: I8a8c2d1437ec77c99588261e3eba0abdcb13c105
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1630448
> Auto-Submit: Marc-Antoine Ruel <maruel@chromium.org>
> Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
> Commit-Queue: Robbie Iannucci <iannucci@chromium.org>

TBR=maruel@chromium.org,iannucci@chromium.org

Change-Id: I206becbf5bde4bb12e9d71ccab13027171fb017f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1633030Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>