Custom Android Grammar SpeechRecognizer or RecognizerIntent

Question

There are a few posts that talk about RecognizerIntent and SpeechRecognizer and that it does not support custom grammar sections. Most of these posts are several years ago. With Google Now, Google seems to be doing this with “ok google,” and I'm wondering if there is a way to do it now.

I also noticed that Nuance seems to be the back of what Android uses for ASR. I know that the news engine supports custom grammar sections and that Google seems to be using them, but are these JNIs open, perhaps in a simple, undocumented way?

I base a lot of these assumptions on this source repository http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.3_r2.1/android/speech/srec/Recognizer. java