audiodecoder: expose default query handling function

Subclasses can use it to select what queries they want to handle
and forward the rest to the default handling function.

API: gst_audio_decoder_sink_query_default

https://bugzilla.gnome.org/show_bug.cgi?id=753623

gst-libs/gst/audio/gstaudiodecoder.c

@@ -383,8 +383,6 @@ static gboolean gst_audio_decoder_negotiate_default (GstAudioDecoder * dec);
 static gboolean gst_audio_decoder_negotiate_unlocked (GstAudioDecoder * dec);
 static gboolean gst_audio_decoder_handle_gap (GstAudioDecoder * dec,
     GstEvent * event);
-static gboolean gst_audio_decoder_sink_query_default (GstAudioDecoder * dec,
-    GstQuery * query);
 static gboolean gst_audio_decoder_src_query_default (GstAudioDecoder * dec,
     GstQuery * query);
 
@@ -2634,7 +2632,19 @@ gst_audio_decoder_sink_getcaps (GstAudioDecoder * decoder, GstCaps * filter)
   return caps;
 }
 
-static gboolean
+/**
+ * gst_audio_decoder_sink_query_default:
+ * @decoder: a #GstAudioDecoder
+ * @query: (transfer none): a #GstQuery
+ *
+ * Calls the default query handler for #GstAudioDecoder. It is useful
+ * when a subclass only want to handle a particular type of query and
+ * wants to use the default handler for others.
+ *
+ * Returns: a boolean, representing if the query was handled.
+ * Since: 1.6
+ */
+gboolean
 gst_audio_decoder_sink_query_default (GstAudioDecoder * dec, GstQuery * query)
 {
   GstPad *pad = GST_AUDIO_DECODER_SINK_PAD (dec);

gst-libs/gst/audio/gstaudiodecoder.h

@@ -394,6 +394,9 @@ void              gst_audio_decoder_get_allocator (GstAudioDecoder * dec,
 void              gst_audio_decoder_merge_tags (GstAudioDecoder * dec,
                                                 const GstTagList * tags, GstTagMergeMode mode);
 
+gboolean          gst_audio_decoder_sink_query_default (GstAudioDecoder * dec,
+                                                        GstQuery * query);
+
 G_END_DECLS
 
 #endif /* _GST_AUDIO_DECODER_H_ */

win32/common/libgstaudio.def

@@ -67,6 +67,7 @@ EXPORTS
 	gst_audio_decoder_set_plc
 	gst_audio_decoder_set_plc_aware
 	gst_audio_decoder_set_tolerance
+	gst_audio_decoder_sink_query_default
 	gst_audio_downmix_meta_api_get_type
 	gst_audio_downmix_meta_get_info
 	gst_audio_encoder_allocate_output_buffer