[Android] Prepare build/android/ for catapult+devil.

build/android/provision_devices.py

Index: build/android/provision_devices.py
diff --git a/build/android/provision_devices.py b/build/android/provision_devices.py
index b9733516da749ec385f045fb4fa1998f1bc7b78f..5f8fce274e6cd15bf6367ad701b80072b4719ab6 100755
--- a/build/android/provision_devices.py
+++ b/build/android/provision_devices.py
@@ -33,6 +33,7 @@ from devil.utils import run_tests_helper
 from devil.utils import timeout_retry
 from pylib import constants
 from pylib import device_settings
+from pylib.constants import host_paths
 
 _SYSTEM_WEBVIEW_PATHS = ['/system/app/webview', '/system/app/WebViewGoogle']
 _CHROME_PACKAGE_REGEX = re.compile('.*chrom.*')
@@ -427,7 +428,7 @@ def _PushAndLaunchAdbReboot(device, target):
   device.KillAll('adb_reboot', blocking=True, timeout=2, quiet=True)
   # Push adb_reboot
   logging.info('  Pushing adb_reboot ...')
-  adb_reboot = os.path.join(constants.DIR_SOURCE_ROOT,
+  adb_reboot = os.path.join(host_paths.DIR_SOURCE_ROOT,
                             'out/%s/adb_reboot' % target)
   device.PushChangedFiles([(adb_reboot, '/data/local/tmp/')])
   # Launch adb_reboot
@@ -442,7 +443,7 @@ def _LaunchHostHeartbeat():
   KillHostHeartbeat()
   # Launch a new host_heartbeat
   logging.info('Spawning host heartbeat...')
-  subprocess.Popen([os.path.join(constants.DIR_SOURCE_ROOT,
+  subprocess.Popen([os.path.join(host_paths.DIR_SOURCE_ROOT,
                                  'build/android/host_heartbeat.py')])
 
 def KillHostHeartbeat():