[Android] Fix device handling in adb_reverse_forwarder.py.

BUG=

Review URL: https://codereview.chromium.org/1898353003

Cr-Original-Commit-Position: refs/heads/master@{#388419}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 884cfea7f0534a79daff21c7493f14647c56c6f1

android/adb_reverse_forwarder.py

@@ -61,8 +61,8 @@ def main(argv):
   blacklist = (device_blacklist.Blacklist(options.blacklist_file)
                if options.blacklist_file
                else None)
-  device = device_utils.DeviceUtils.HealthyDevices(blacklist=blacklist,
-                                                   device_arg=options.device)
+  device = device_utils.DeviceUtils.HealthyDevices(
+      blacklist=blacklist, device_arg=options.device)[0]
   constants.SetBuildType(options.build_type)
   try:
     forwarder.Forwarder.Map(port_pairs, device)