Revert of Enabling `gn check` on webrtc/test (patchset #9 id:160001 of https://codereview.webrtc.org/2911203002/ )

Reason for revert:
ERROR at //webrtc/test/testsupport/fileutils_unittest.cc:20:11: Can't include this header from here.
#include "webrtc/base/checks.h"
          ^-------------------
The target:
  //webrtc/test:fileutils_unittests
is including a file from the target:
  //webrtc/base:rtc_base_approved

It's usually best to depend directly on the destination target.
In some cases, the destination target is considered a subcomponent
of an intermediate target. In this case, the intermediate target
should depend publicly on the destination to forward the ability
to include headers.

Dependency chain (there may also be others):
  //webrtc/test:fileutils_unittests -->
  //webrtc/test:fileutils --[private]-->
  //webrtc/base:rtc_base_approved

Original issue's description:
> Enabling `gn check` on webrtc/test
>
> BUG=webrtc:6828
> NOTRY=True
>
> Review-Url: https://codereview.webrtc.org/2911203002
> Cr-Commit-Position: refs/heads/master@{#18372}
> Committed: https://chromium.googlesource.com/external/webrtc/+/db5bb404b0f42a7c0a43f882b34ba1325d8cbae2

TBR=kjellander@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6828

Review-Url: https://codereview.webrtc.org/2920763002
Cr-Commit-Position: refs/heads/master@{#18375}

1 files changed, 0 insertions, 1 deletions

diff --git a/.gn b/.gn
index 70a0c3e45e..a6b4af7280 100644
--- a/.gn
+++ b/.gn
@@ -37,7 +37,6 @@ check_targets = [
   "//webrtc/sdk/*",
   "//webrtc/stats/*",
   "//webrtc/system_wrappers/*",
-  "//webrtc/test/*",
   "//webrtc/tools/*",
   "//webrtc/video/*",
   "//webrtc/voice_engine/*",