Expose ability to download network service impl in SDK.

mojo/tools/roll/roll_network_service.py

 #!/usr/bin/env python
 # Copyright 2015 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 argparse
 import os
 import subprocess
 import sys
 import tempfile
@@ skipping 15 matching lines @@
   except urllib2.HTTPError:
     print ("Failed to identify a Chromium revision associated with %s. "
            "Ensure that target_version is a Chromium origin/master "
            "commit.") % (target_version)
     return 1
 
   mojoms_gs_path = "gs://mojo/network_service/%s/mojoms.zip" % (target_version,)
   network_service_path = os.path.join(
       mojo_root_dir, "mojo", "services", "network")
   mojoms_path = os.path.join(network_service_path, "public", "interfaces")
-  version_path = os.path.join(network_service_path, "VERSION")
+  mojo_public_tools_path = os.path.join(
+      mojo_root_dir, "mojo", "public", "tools")
+  version_path = os.path.join(mojo_public_tools_path, "NETWORK_SERVICE_VERSION")
 
   try:
     with tempfile.NamedTemporaryFile() as temp_zip_file:
       gs.download_from_public_bucket(mojoms_gs_path, temp_zip_file.name)
 
       try:
         system(["git", "rm", "-r", mojoms_path], cwd=mojo_root_dir)
       except subprocess.CalledProcessError:
         print ("Could not remove %s. "
                "Ensure your local tree is in a clean state." % mojoms_path)
         return 1
 
       with zipfile.ZipFile(temp_zip_file.name) as z:
         z.extractall(mojoms_path)
   # pylint: disable=C0302,bare-except
   except:
     print ("Failed to download the mojom files associated with %s. Ensure that "
            "the corresponding network service artifacts were uploaded to "
            "Google Storage.") % (target_version)
     return 1
 
   with open(version_path, 'w') as stamp_file:
     stamp_file.write(target_version)
 
   system(["git", "add", "public"], cwd=network_service_path)
-  system(["git", "add", "VERSION"], cwd=network_service_path)
+  system(["git", "add", "NETWORK_SERVICE_VERSION"], cwd=mojo_public_tools_path)
   commit("Roll the network service to https://crrev.com/" + chromium_rev,
          cwd=mojo_root_dir)
   return 0
 
 def main():
   parser = argparse.ArgumentParser(
       description="Update the pinned version of the network service " +
                   "and the corresponding checked out mojoms.")
   parser.add_argument("version", help="version to roll to (a Chromium "
                                       "origin/master commit)")
   args = parser.parse_args()
   roll(args.version)
   return 0
 
 if __name__ == "__main__":
   sys.exit(main())