Fix Bitreader "putBits" implementation, make sure we emulate timestamps

if we don't receive npt time mapping from the rtsp server (i.e. live stream)

Change-Id: I5147d665bd90c9a303ad6ffdafbf770f930f917c
related-to-bug: 5660357
diff --git a/media/libmediaplayerservice/nuplayer/RTSPSource.h b/media/libmediaplayerservice/nuplayer/RTSPSource.h
index 66eab72..a401caa 100644
--- a/media/libmediaplayerservice/nuplayer/RTSPSource.h
+++ b/media/libmediaplayerservice/nuplayer/RTSPSource.h
@@ -76,6 +76,7 @@
         int32_t mTimeScale;
         uint32_t mRTPTime;
         int64_t mNormalPlaytimeUs;
+        bool mNPTMappingValid;
     };
 
     AString mURL;