Make the fuchsia mojo/public repo the source of truth.

mojo/public/tools/prepend.py

-#!/usr/bin/env python
-#
-# Copyright 2014 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.
-
-"""
-Prepends a given file with a given line. This can be used to add a shebang line
-to a generated file.
-"""
-
-import optparse
-import os
-import shutil
-import sys
-
-
-def main():
-  parser = optparse.OptionParser()
-  parser.add_option('--input', help='The file to prepend the line to.')
-  parser.add_option('--line', help='The line to be prepended.')
-  parser.add_option('--output', help='The output file.')
-
-  options, _ = parser.parse_args()
-  input_path = options.input
-  output_path = options.output
-  line = options.line
-
-  # Warning - this reads all of the input file into memory.
-  with open(output_path, 'w') as output_file:
-    output_file.write(line + '\n')
-    with open(input_path, 'r') as input_file:
-      shutil.copyfileobj(input_file, output_file)
-
-
-if __name__ == '__main__':
-  sys.exit(main())