Bump versionCode of SkyDemo.apk to avoid downgrade warning.

sky/tools/shelldb

 #!/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.
 
 from skypy.skyserver import SkyServer
 import argparse
 import json
 import logging
 import os
@@ skipping 157 matching lines @@
         ])
 
         sky_server = self._sky_server_for_args(args, packages_root)
         pids['sky_server_pid'] = sky_server.start()
         pids['sky_server_port'] = sky_server.port
         pids['sky_server_root'] = sky_server.root
 
         pids['build_dir'] = os.path.abspath(args.build_dir)
 
         if args.install:
-            subprocess.check_call([ADB_PATH, 'install', '-r', apk_path])
+            # -r to replace an existing apk, -d to allow version downgrade.
+            subprocess.check_call([ADB_PATH, 'install', '-r', '-d', apk_path])
 
         port_string = 'tcp:%s' % sky_server.port
         subprocess.check_call([
             ADB_PATH, 'reverse', port_string, port_string
         ])
         pids['remote_sky_server_port'] = sky_server.port
 
         subprocess.check_call([ADB_PATH, 'shell',
             'am', 'start',
             '-a', 'android.intent.action.VIEW',
@@ skipping 122 matching lines @@
         args = parser.parse_args()
         pids = Pids.read_from(PID_FILE_PATH, PID_FILE_KEYS)
         exit_code = args.func(args, pids)
         # We could do this with an at-exit handler instead?
         pids.write_to(PID_FILE_PATH)
         sys.exit(exit_code)
 
 
 if __name__ == '__main__':
     SkyShellRunner().main()