clapper: Do not reset "adaptive-bandwidth" to zero

When new instance of adaptive demuxer is created (different video is played)
this prop value would become zero. We want to avoid that and instead report
only bandwidth after fragment is downloaded, so when video will be unplayable,
next one will not start from lowest quality.

src/lib/clapper/clapper-player.c

@@ -726,6 +726,11 @@ _adaptive_demuxer_bandwidth_changed_cb (GstElement *adaptive_demuxer,
 
   g_object_get (adaptive_demuxer, "current-bandwidth", &bandwidth, NULL);
 
+  /* Skip uncalculated bandwidth from
+   * new adaptive demuxer instance */
+  if (bandwidth == 0)
+    return;
+
   GST_OBJECT_LOCK (self);
   if ((changed = bandwidth != self->bandwidth))
     self->bandwidth = bandwidth;