Forward the Observatory port in sky_tool

sky/sdk/lib/sky_tool

 #!/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 json
 import logging
 import os
 import re
 import signal
 import socket
 import subprocess
 import sys
 import urlparse
 import time
 
 # TODO(eseidel): This should be BIN_DIR.
 LIB_DIR = os.path.realpath(os.path.dirname(os.path.abspath(__file__)))
 SKY_PACKAGE_ROOT = os.path.realpath(os.path.dirname(LIB_DIR))
 
 SKY_SERVER_PORT = 9888
+OBSERVATORY_PORT = 8181
 APK_NAME = 'SkyDemo.apk'
 ANDROID_PACKAGE = "org.domokit.sky.demo"
 # FIXME: This assumes adb is in $PATH, we could look for ANDROID_HOME, etc?
 ADB_PATH = 'adb'
 # FIXME: Do we need to look in $DART_SDK?
 DART_PATH = 'dart'
 
 PID_FILE_PATH = "/tmp/sky_tool.pids"
 PID_FILE_KEYS = frozenset([
     'remote_sky_server_port',
@@ skipping 129 matching lines @@
             args.install = True
 
         if args.install:
             apk_path = os.path.join(SKY_PACKAGE_ROOT, 'apks', APK_NAME)
             if not os.path.exists(apk_path):
                 print "'%s' does not exist?" % apk_path
                 return 2
 
             subprocess.check_call([ADB_PATH, 'install', '-r', apk_path])
 
+        # Set up port forwarding for observatory
+        observatory_port_string = 'tcp:%s' % OBSERVATORY_PORT
+        subprocess.check_call([
+            ADB_PATH, 'forward', observatory_port_string, observatory_port_string
+        ])
+
         sky_server_port = SKY_SERVER_PORT
         pids['sky_server_port'] = sky_server_port
         if _port_in_use(sky_server_port):
             logging.warn(('Port %s already in use. '
             ' Not starting server for %s') % (sky_server_port, sky_server_root))
         else:
             sky_server_pid = _start_http_server(sky_server_port, sky_server_root)
             pids['sky_server_pid'] = sky_server_pid
             pids['sky_server_root'] = sky_server_root
 
@@ skipping 119 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()