NuPlayerRenderer: return correct pending audio duration for virtual audio sink.

Bug: 27222912
Change-Id: Ia900f8ac66fcdad538f847233fe680f6bf47ea2f
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
index 1bc9c97..c3ce511 100644
--- a/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerRenderer.h
@@ -134,6 +134,7 @@
     static const int64_t kMinPositionUpdateDelayUs;
 
     sp<MediaPlayerBase::AudioSink> mAudioSink;
+    bool mUseVirtualAudioSink;
     sp<AMessage> mNotify;
     Mutex mLock;
     uint32_t mFlags;