Add a fetch config for chrome (internal).

Although many things are private, the existence of Chrome is not.
This change has precedent, c.f. 04d16a56 for infra_internal.

Bug: None
Change-Id: I6fb9719a44c2e5f5cc492bacb442d9554b0d4480
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3779641Reviewed-by: Aravind Vasudevan <aravindvasudev@google.com>
Commit-Queue: Thiago Perrotta <tperrotta@chromium.org>
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Aravind Vasudevan <aravindvasudev@google.com>

fetch_configs/chrome.py

+# Copyright (c) 2022 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import sys
+
+import config_util  # pylint: disable=import-error
+
+
+# This class doesn't need an __init__ method, so we disable the warning
+# pylint: disable=no-init
+class Chrome(config_util.Config):
+  """Basic Config alias for Chrome -> Chromium."""
+
+  @staticmethod
+  def fetch_spec(props):
+    return {
+      'alias': {
+        'config': 'chromium',
+        'props': [
+            '--internal=True',
+        ],
+      },
+    }
+
+  @staticmethod
+  def expected_root(_props):
+    return ''
+
+
+def main(argv=None):
+  return Chrome().handle_args(argv)
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))