[Android] Remove more uses of android_commands from build/android/pylib.

build/android/test_runner.py

Index: build/android/test_runner.py
diff --git a/build/android/test_runner.py b/build/android/test_runner.py
index c54ed28d324054eae3c5aee72aa1442d80bf1f36..f3dd764e554929b40f364460259038599549d4e6 100755
--- a/build/android/test_runner.py
+++ b/build/android/test_runner.py
@@ -16,7 +16,6 @@ import sys
 import threading
 import unittest
 
-from pylib import android_commands
 from pylib import constants
 from pylib import forwarder
 from pylib import ports
@@ -25,6 +24,8 @@ from pylib.base import environment_factory
 from pylib.base import test_dispatcher
 from pylib.base import test_instance_factory
 from pylib.base import test_run_factory
+from pylib.device import device_errors
+from pylib.device import device_utils
 from pylib.gtest import gtest_config
 from pylib.gtest import setup as gtest_setup
 from pylib.gtest import test_options as gtest_test_options
@@ -867,16 +868,16 @@ def _GetAttachedDevices(test_device=None):
   Returns:
     A list of attached devices.
   """
-  attached_devices = []
-
-  attached_devices = android_commands.GetAttachedDevices()
+  attached_devices = device_utils.DeviceUtils.HealthyDevices()
   if test_device:
-    assert test_device in attached_devices, (
-        'Did not find device %s among attached device. Attached devices: %s'
-        % (test_device, ', '.join(attached_devices)))
-    attached_devices = [test_device]
-
-  assert attached_devices, 'No devices attached.'
+    test_device = [d for d in attached_devices if d == test_device]
+    if not test_device:
+      raise device_errors.DeviceUnreachableError(
+          'Did not find device %s among attached device. Attached devices: %s'
+          % (test_device, ', '.join(attached_devices)))
+
+  if not attached_devices:
+    raise device_errors.NoDevicesError()
 
   return sorted(attached_devices)