Sky shelldb should restart app when using --no_install and forward observatory port

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
 import re
 import signal
 import subprocess
 import sys
 import time
 import urlparse
 
 SKY_TOOLS_DIR = os.path.dirname(os.path.abspath(__file__))
 SKY_ROOT = os.path.dirname(SKY_TOOLS_DIR)
 SRC_ROOT = os.path.dirname(SKY_ROOT)
 
 SKY_SERVER_PORT = 9888
+OBSERVATORY_PORT = 8181
 DEFAULT_URL = "sky://domokit.github.io/sky_home"
 APK_NAME = 'SkyDemo.apk'
 ADB_PATH = os.path.join(SRC_ROOT,
     'third_party/android_tools/sdk/platform-tools/adb')
 ANDROID_PACKAGE = "org.domokit.sky.demo"
 
 PID_FILE_PATH = "/tmp/skydemo.pids"
 PID_FILE_KEYS = frozenset([
     'remote_sky_server_port',
     'sky_server_pid',
@@ skipping 154 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:
             # -r to replace an existing apk, -d to allow version downgrade.
             subprocess.check_call([ADB_PATH, 'install', '-r', '-d', apk_path])
+        else:
+            subprocess.check_call([
+                ADB_PATH, 'shell', 'am', 'force-stop', ANDROID_PACKAGE
+            ])
+
+        # Set up port forwarding for observatory
+        port_string = 'tcp:%s' % OBSERVATORY_PORT
+        subprocess.check_call([
+            ADB_PATH, 'forward', port_string, port_string
+        ])
 
         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 141 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()