This reverts commit b7ddc5a0.

Reason for revert:
This broke the builder where depot_tools is not in PATH.
https://logs.chromium.org/logs/infra-internal/buildbucket/cr-buildbucket.appspot.com/8858077852309878080/+/u/build/stdout

Original change's description:
> Check whether goma is running when it is enabled
>
> One of the mistakes one can make when running ninja is having goma
> enabled (use_goma=true in args.gn) but not having goma running. This can
> lead to ~1,000 failed compile steps, which is messy.
>
> This change teaches autoninja.py to check whether goma is running. If
> not then it tells autoninja to just print a warning message. The
> check costs roughly 30 ms which seems reasonable.
>
> In fact, because this change also switches away from vpython (necessary
> to use python3 to use subprocess.run) it actually runs about 600 ms
> _faster_ than before this change.
>
> If build acceleration is requested through use_rbe then no checking for
> whether the service is running is done. That could be added in the
> future.
>
> autoninja.py could auto-start goma but that is error prone and has
> limited additional value.
>
> This was tested on Linux, OSX, and Windows.
>
> Bug: 868590, b/174673874
> Change-Id: Ie773e574878471e5136b9b82d52f86af3d848318
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2627014
> Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
> Reviewed-by: Yoshisato Yanagisawa <yyanagisawa@google.com>

TBR=yyanagisawa@google.com,dpranke@google.com,brucedawson@chromium.org,sanfin@chromium.org,infra-scoped@luci-project-accounts.iam.gserviceaccount.com

Change-Id: I57a6c73ea853259f3d1ec7ad0ce51e495acc96db
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 868590
Bug: b/174673874
Bug: 1167064
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2632018Reviewed-by: Yoshisato Yanagisawa <yyanagisawa@google.com>
Commit-Queue: Yoshisato Yanagisawa <yyanagisawa@google.com>