Add the beginnings of scripts to produce SDKs.

sdk_build/pylib/errors.py

Index: sdk_build/pylib/errors.py
diff --git a/sdk_build/pylib/errors.py b/sdk_build/pylib/errors.py
new file mode 100644
index 0000000000000000000000000000000000000000..f90abfdcd97fdb8b9191461a7e33a0e3d4b8c99d
--- /dev/null
+++ b/sdk_build/pylib/errors.py
@@ -0,0 +1,15 @@
+# Copyright 2016 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.
+
+"""Error-handling support functions."""
+
+
+import os.path
+import sys
+
+
+def FatalError(message):
+  print >> sys.stderr, "%s: fatal error: %s" % (os.path.basename(sys.argv[0]),
+                                                message)
+  sys.exit(1)