Revert of Stop silently accepting unsupported flags in test binaries (patchset #5 id:150001 of https://codereview.webrtc.org/2968003003/ )

Reason for revert:
Causes failures on perf bots
https://luci-milo.appspot.com/buildbot/client.webrtc.perf/Mac%2010.11/3567

Original issue's description:
> Stop silently accepting unsupported flags in test binaries
>
> Instead explicitly ignore only the flags we know should be ignored.
>
> BUG=webrtc:7568
>
> Review-Url: https://codereview.webrtc.org/2968003003
> Cr-Commit-Position: refs/heads/master@{#19412}
> Committed: a2782f6f5d

TBR=kjellander@webrtc.org,henrika@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:7568

Review-Url: https://codereview.webrtc.org/3002963002
Cr-Commit-Position: refs/heads/master@{#19413}

tools_webrtc/gtest-parallel-wrapper.py

@@ -81,10 +81,6 @@ def get_args_and_env():
   parser.add_argument('--isolated-script-test-chartjson-output', type=str,
                       default=None)
 
-  # No-sandbox is a Chromium-specific flag, ignore it.
-  # TODO(oprypin): Remove (bugs.webrtc.org/8115)
-  parser.add_argument('--no-sandbox', action='store_true', default=False)
-
   # We have to do this, since --isolated-script-test-output is passed as an
   # argument to the executable by the swarming scripts, and we want to pass it
   # to gtest-parallel instead.