[Android] Update the manifest json parser as the changed field of "app".

1 Change the parsing process for the changed field from "launch_path"
  to "app/launch/local_path".
2 The further change will follow the manifest specification to be finalized.

BUG=#778
Merge pull request #780 from ShDavidliu/master

[Android] Update the manifest json parser as the changed field of "app".