Attempt to stop sky_server before starting it to avoid confusion and the warning message.

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 hashlib
 import json
 import logging
@@ skipping 162 matching lines @@
         pm_output = subprocess.check_output(pm_command)
         # e.g. package:/data/app/org.chromium.mojo.shell-1/base.apk
         return pm_output.split(':')[-1]
 
     def run(self, args, pids):
         apk_path = os.path.join(args.build_dir, 'apks', APK_NAME)
         if not os.path.exists(apk_path):
             print "'%s' does not exist?" % apk_path
             return 2
 
+        StopSky().run(args, pids)
+
         packages_root = dev_packages_root(args.build_dir)
         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:
             # We might need to install a new APK, so check SHA1
@@ skipping 182 matching lines @@
         port_string = 'tcp:%s' % port
         subprocess.call([ADB_PATH, 'forward', '--remove', port_string])
 
     def run(self, args, pids):
         self._kill_if_exists(pids, 'sky_server_pid', 'sky_server')
 
         if 'remote_sky_server_port' in pids:
             self._adb_reverse_remove(pids['remote_sky_server_port'])
 
         if 'remote_gdbserver_port' in pids:
-            self._kill_if_exists('adb_shell_gdbserver_pid',
-                'adb shell gdbserver')
             self._adb_forward_remove(pids['remote_gdbserver_port'])
 
         subprocess.call([
             ADB_PATH, 'shell', 'am', 'force-stop', ANDROID_PACKAGE])
 
         pids.clear()
 
 
 class Analyze(object):
     def add_subparser(self, subparsers):
@@ skipping 96 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()