Upgrade analyze.py and related scripts to new world order.

tools/android/loading/device_setup.py

 # Copyright 2016 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 contextlib
+import logging
 import os
 import sys
 import time
 
 _SRC_DIR = os.path.abspath(os.path.join(
     os.path.dirname(__file__), '..', '..', '..'))
 
 sys.path.append(os.path.join(_SRC_DIR, 'third_party', 'catapult', 'devil'))
+from devil.android import device_utils
 from devil.android.sdk import intent
 
 sys.path.append(os.path.join(_SRC_DIR, 'build', 'android'))
 from pylib import constants
 from pylib import flag_changer
 
 import devtools_monitor
 
 DEVTOOLS_PORT = 9222
 DEVTOOLS_HOSTNAME = 'localhost'
 DEFAULT_CHROME_PACKAGE = 'chrome'
 
+
+class DeviceSetupException(Exception):
+  def __init__(self, msg):
+    super(DeviceSetupException, self).__init__(msg)
+    logging.error(msg)
+
+
+def GetFirstDevice():
+  """Returns the first connected device.
+
+  Raises:
+    DeviceSetupException if there is no such device.
+  """
+  devices = device_utils.DeviceUtils.HealthyDevices()
+  if not devices:
+    raise DeviceSetupException('No devices found')
+  return devices[0]
+
+
 @contextlib.contextmanager
 def FlagReplacer(device, command_line_path, new_flags):
   """Replaces chrome flags in a context, restores them afterwards.
 
   Args:
     device: Device to target, from DeviceUtils. Can be None, in which case this
       context manager is a no-op.
     command_line_path: Full path to the command-line file.
     new_flags: Flags to replace.
   """
@@ skipping 77 matching lines @@
     package: the key for chrome package info.
     fn: the function to execute that launches chrome and performs the
         appropriate instrumentation. The function will receive a
         DevToolsConnection as its sole parameter.
 
   Returns:
     As fn() returns.
   """
   with DeviceConnection(device, package) as connection:
     return fn(connection)