Add fetch configs for devtools-frontend

Change-Id: Ib416a8a00c57c21d31d16d928932fcd16f39426f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1903486
Commit-Queue: Aaron Gable <agable@chromium.org>
Reviewed-by: Aaron Gable <agable@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Auto-Submit: Yang Guo <yangguo@chromium.org>

fetch_configs/devtools-frontend.py

+# Copyright 2019 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 DevToolsFrontend(config_util.Config):
+  """Basic Config class for DevTools frontend."""
+
+  @staticmethod
+  def fetch_spec(props):
+    url = 'https://chromium.googlesource.com/devtools/devtools-frontend.git'
+    solution = {
+        'name'        : 'devtools-frontend',
+        'url'         : url,
+        'deps_file'   : 'DEPS',
+        'managed'     : False,
+        'custom_deps' : {},
+    }
+    spec = {
+      'solutions': [solution],
+      'with_branch_heads': True,
+    }
+    return {
+      'type': 'gclient_git',
+      'gclient_git_spec': spec,
+    }
+
+  @staticmethod
+  def expected_root(_props):
+    return 'devtools-frontend'
+
+
+def main(argv=None):
+  return DevToolsFrontend().handle_args(argv)
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))