Revert "Add wrapper to normalize flags."

This reverts commit 642a49d1eb20b8c5744e745de79ddb585e0f7472.

Reason for revert: Speculative revert, may cause infra failures on perf waterfall

Original change's description:
> Add wrapper to normalize flags.
>
> Bug: None
> Change-Id: I9d43602cc66198a29dbc0e7586d948ee76c5ec84
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/145204
> Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
> Reviewed-by: Oleh Prypin <oprypin@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#28532}

TBR=mbonadei@webrtc.org,oprypin@webrtc.org

# Not skipping CQ checks because original CL landed > 1 day ago.

No-Try: True
Bug: None
Change-Id: I1a559931b51b2b4614e765978200d47ee37f9186
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/145328
Commit-Queue: Artem Titarenko <artit@webrtc.org>
Reviewed-by: Artem Titarenko <artit@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28554}
diff --git a/BUILD.gn b/BUILD.gn
index d3c1ed5..af0de9f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -609,8 +609,7 @@
       "video:video_pc_full_stack_tests",
     ]
 
-    data =
-        webrtc_perf_tests_resources + [ "tools_webrtc/flags_compatibility.py" ]
+    data = webrtc_perf_tests_resources
     if (is_android) {
       deps += [ "//testing/android/native_test:native_test_native_code" ]
       shard_timeout = 4500
diff --git a/tools_webrtc/flags_compatibility.py b/tools_webrtc/flags_compatibility.py
deleted file mode 100644
index a1639c2..0000000
--- a/tools_webrtc/flags_compatibility.py
+++ /dev/null
@@ -1,37 +0,0 @@
-#!/usr/bin/env python
-
-# Copyright (c) 2019 The WebRTC project authors. All Rights Reserved.
-#
-# Use of this source code is governed by a BSD-style license
-# that can be found in the LICENSE file in the root of the source
-# tree. An additional intellectual property rights grant can be found
-# in the file PATENTS.  All contributing project authors may
-# be found in the AUTHORS file in the root of the source tree.
-
-import argparse
-import logging
-import subprocess
-import sys
-
-def main():
-  parser = argparse.ArgumentParser()
-  parser.add_argument('--isolated-script-test-output')
-  parser.add_argument('--isolated-script-test-perf-output')
-  args, unrecognized_args = parser.parse_known_args()
-
-  test_command = unrecognized_args
-  if args.isolated_script_test_output:
-    test_command += ['--isolated_script_test_output',
-                     args.isolated_script_test_output]
-  if args.isolated_script_test_perf_output:
-    test_command += ['--isolated_script_test_perf_output',
-                     args.isolated_script_test_perf_output]
-  logging.info('Running %r', test_command)
-
-  return subprocess.call(test_command)
-
-
-if __name__ == '__main__':
-  # pylint: disable=W0101
-  logging.basicConfig(level=logging.INFO)
-  sys.exit(main())
diff --git a/tools_webrtc/mb/gn_isolate_map.pyl b/tools_webrtc/mb/gn_isolate_map.pyl
index 0b49ca9..43bdc17 100644
--- a/tools_webrtc/mb/gn_isolate_map.pyl
+++ b/tools_webrtc/mb/gn_isolate_map.pyl
@@ -127,10 +127,6 @@
   "webrtc_perf_tests": {
     "label": "//:webrtc_perf_tests",
     "timeout": 3600,  # 1 hour
-    "type": "script",
-    "script": "//tools_webrtc/flags_compatibility.py",
-    "args": [
-      "./webrtc_perf_tests",
-    ],
+    "type": "raw",
   },
 }