[build/android] Fix error messages in adb_install_apk

`args.apk_name` is deprecated, the name/path of the apk to install is
now always stored in `apk`.

TBR=jbudorick@chromium.org

Bug: 736913
Change-Id: Iba9ca473e4f803c67efd3d434ac6f60565a90e10
Reviewed-on: https://chromium-review.googlesource.com/558909
Reviewed-by: Juan Antonio Navarro Pérez <perezju@chromium.org>
Commit-Queue: Juan Antonio Navarro Pérez <perezju@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#483996}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 875e44e54911cd34831c21db586202c87fbe3ba5

android/adb_install_apk.py

@@ -115,12 +115,12 @@ def main():
                        timeout=args.timeout)
     except (device_errors.CommandFailedError,
             device_errors.DeviceUnreachableError):
-      logging.exception('Failed to install %s', args.apk_name)
+      logging.exception('Failed to install %s', apk)
       if blacklist:
         blacklist.Extend([str(device)], reason='install_failure')
         logging.warning('Blacklisting %s', str(device))
     except device_errors.CommandTimeoutError:
-      logging.exception('Timed out while installing %s', args.apk_name)
+      logging.exception('Timed out while installing %s', apk)
       if blacklist:
         blacklist.Extend([str(device)], reason='install_timeout')
         logging.warning('Blacklisting %s', str(device))