CC-5226: Metadata isn't correct during playing

-fixed using "insert_metadata" and callbacks instead.

python_apps/pypo/liquidsoap_scripts/ls_lib.liq

@@ -5,7 +5,8 @@ def notify(m)
 end
 
 def notify_queue(m)
-  queue_metadata := m
+  f = !dynamic_metadata_callback
+  ignore(f(m))
   notify(m)
 end
 
@@ -31,10 +32,6 @@ def append_title(m) =
   end
 end
 
-def queue_metadata_callback(m) =
-    !queue_metadata
-end
-
 def crossfade_airtime(s)
   #duration is automatically overwritten by metadata fields passed in
   #with audio

python_apps/pypo/liquidsoap_scripts/ls_script.liq

@@ -24,7 +24,7 @@ default_dj_fade = ref 0.
 station_name = ref ''
 show_name = ref ''
 
-queue_metadata = ref []
+dynamic_metadata_callback = ref fun (s) -> begin () end
 
 s1_connected = ref ''
 s2_connected = ref ''
@@ -72,7 +72,11 @@ create_source()
 
 queue = add(!sources, normalize=false)
 
-queue = map_metadata(update=false, queue_metadata_callback, queue)
+pair = insert_metadata(queue)
+f = fst(pair)
+queue = snd(pair)
+
+dynamic_metadata_callback := f
 
 output.dummy(fallible=true, queue)