Vorbis render thread was nice 0, should be nice -16.

Seems like a recent change sets the thread priority to 0. Previously it
inherited priority from the parent thread. This change sets the Vorbis
render thread priority to the default for audio threads.
Reference bug 1800905

media/libmediaplayerservice/VorbisPlayer.cpp

@@ -67,7 +67,7 @@ void VorbisPlayer::onFirstRef()
     LOGV("onFirstRef");
     // create playback thread
     Mutex::Autolock l(mMutex);
-    createThreadEtc(renderThread, this, "vorbis decoder");
+    createThreadEtc(renderThread, this, "vorbis decoder", ANDROID_PRIORITY_AUDIO);
     mCondition.wait(mMutex);
     if (mRenderTid > 0) {
         LOGV("render thread(%d) started", mRenderTid);