gn2bp: add copy of perfetto project gn to bp tooling

This will serve as a starting point to generate Android.bp files for
cronet.

Test: n/a
Change-Id: Ia5ccad48f705fd48cff212dbedbfb61b6e385468
diff --git a/tools/gn2bp/compat.py b/tools/gn2bp/compat.py
new file mode 100755
index 0000000..db587a2
--- /dev/null
+++ b/tools/gn2bp/compat.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+# Copyright (C) 2022 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+try:
+  from shlex import quote
+except ImportError:
+  from pipes import quote
+
+try:
+  from urllib.request import urlretrieve
+except ImportError:
+  from urllib import urlretrieve
+
+try:
+  xrange = xrange
+except NameError:
+  xrange = range
+
+try:
+  basestring = basestring
+except NameError:
+  basestring = str
+
+
+def itervalues(o):
+  try:
+    return o.itervalues()
+  except AttributeError:
+    return o.values()
+
+
+def iteritems(o):
+  try:
+    return o.iteritems()
+  except AttributeError:
+    return o.items()