private void reactVideoBufferStartCallback() {
        mReactContext.getJSModule(RCTEventEmitter.class).receiveEvent(
                getId(),
                ViroEvents.ON_BUFFER_START,
                null);
    }
Contains a VideoTexture that is set as a background video on the scene.
android/viro_bridge/src/main/java/com/viromedia/bridge/component/VRT360Video.java