Partial revert of flag simplification.

Unfortunately it turns out the Android test runner requires
the isolated script flag to be in its current form, or it
doesn't work. This means we have to keep translating the
flag name.

We can get rid of the isolated_script_test_output flag
at least.

Tbr: mbonadei@webrtc.org
Bug: chromium:1051927
Change-Id: I4fdbff980e65332b757b1c95aa6587328411c0ed
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/171809
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Patrik Höglund <phoglund@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30907}

tools_webrtc/flags_compatibility.py

@@ -0,0 +1,44 @@
+#!/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-perf-output')
+  args, unrecognized_args = parser.parse_known_args()
+
+  test_command = _ForcePythonInterpreter(unrecognized_args)
+  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)
+
+
+def _ForcePythonInterpreter(cmd):
+  """Returns the fixed command line to call the right python executable."""
+  out = cmd[:]
+  if out[0] == 'python':
+    out[0] = sys.executable
+  elif out[0].endswith('.py'):
+    out.insert(0, sys.executable)
+  return out
+
+
+if __name__ == '__main__':
+  # pylint: disable=W0101
+  logging.basicConfig(level=logging.INFO)
+  sys.exit(main())