Revert of [Telemetry] Remove adb_commands usage from android_device.

tools/telemetry/telemetry/core/platform/android_device.py

Index: tools/telemetry/telemetry/core/platform/android_device.py
diff --git a/tools/telemetry/telemetry/core/platform/android_device.py b/tools/telemetry/telemetry/core/platform/android_device.py
index 2584b090a3cbb815125a72fa74408af64b2e5c5e..b5732526fbed68511de562030e4c35bc5ebf88a6 100644
--- a/tools/telemetry/telemetry/core/platform/android_device.py
+++ b/tools/telemetry/telemetry/core/platform/android_device.py
@@ -3,15 +3,14 @@
 # found in the LICENSE file.
 import logging
 import os
+import re
+import subprocess
+import sys
 
 from telemetry.core.platform import device
 from telemetry.core.platform.profiler import monsoon
 from telemetry.core import util
-
-util.AddDirToPythonPath(util.GetChromiumSrcDir(), 'build', 'android')
-from pylib import constants # pylint: disable=import-error
-from pylib.device import device_errors # pylint: disable=import-error
-from pylib.device import device_utils # pylint: disable=import-error
+from telemetry.internal.backends import adb_commands
 
 
 class AndroidDevice(device.Device):
@@ -43,10 +42,9 @@
   def enable_performance_mode(self):
     return self._enable_performance_mode
 
+
 def GetDeviceSerials():
-  device_serials = [d.adb.GetDeviceSerial()
-                    for d in device_utils.DeviceUtils.HealthyDevices()]
-
+  device_serials = adb_commands.GetAttachedDevices()
   # The monsoon provides power for the device, so for devices with no
   # real battery, we need to turn them on after the monsoon enables voltage
   # output to the device.
@@ -67,9 +65,8 @@
 
 Waiting for device...
 """)
-      util.WaitFor(device_utils.DeviceUtils.HealthyDevices, 600)
-      device_serials = [d.adb.GetDeviceSerial()
-                        for d in device_utils.DeviceUtils.HealthyDevices()]
+      util.WaitFor(adb_commands.GetAttachedDevices, 600)
+      device_serials = adb_commands.GetAttachedDevices()
     except IOError:
       return []
   return device_serials
@@ -101,15 +98,33 @@
 
 def CanDiscoverDevices():
   """Returns true if devices are discoverable via adb."""
-  adb_path = constants.GetAdbPath()
-  if os.path.isabs(adb_path) and not os.path.exists(adb_path):
+  if not adb_commands.IsAndroidSupported():
+    logging.info(
+        'Android build commands unavailable on this machine. '
+        'Have you installed Android build dependencies?')
     return False
   try:
-    device_utils.DeviceUtils.HealthyDevices()
+    with open(os.devnull, 'w') as devnull:
+      adb_process = subprocess.Popen(
+          ['adb', 'devices'], stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+          stdin=devnull)
+      stdout = adb_process.communicate()[0]
+    if re.search(re.escape('????????????\tno permissions'), stdout) != None:
+      logging.warn('adb devices gave a permissions error. '
+                   'Consider running adb as root:')
+      logging.warn('  adb kill-server')
+      logging.warn('  sudo `which adb` devices\n\n')
     return True
-  except (device_errors.CommandFailedError, device_errors.CommandTimeoutError,
-          OSError):
-    return False
+  except OSError:
+    pass
+  chromium_adb_path = os.path.join(
+      util.GetChromiumSrcDir(), 'third_party', 'android_tools', 'sdk',
+      'platform-tools', 'adb')
+  if sys.platform.startswith('linux') and os.path.exists(chromium_adb_path):
+    os.environ['PATH'] = os.pathsep.join(
+        [os.path.dirname(chromium_adb_path), os.environ['PATH']])
+    return True
+  return False
 
 
 def FindAllAvailableDevices(_):