[rhythmbox] gst-helper: fix xfade playback with GStreamer 1.18+

[Jonathan Matthew <jmatthew src gnome org>]

commit 3360f18d15cd6fabcadac56bc07d4ca133fa661f
Author: Jonathan Matthew <jonathan d14n org>
Date:   Thu Nov 5 22:41:39 2020 +1000

    gst-helper: fix xfade playback with GStreamer 1.18+
    
    In 1.18, the identity element now provides a clock for the pipeline
    based on the system clock, which screws up timing in the output
    section of the xfade pipeline.  Switching to volume avoids this, and
    since it's left in passthrough mode, doesn't cost us anything.

 backends/gstreamer/rb-player-gst-helper.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/backends/gstreamer/rb-player-gst-helper.c b/backends/gstreamer/rb-player-gst-helper.c
index ae7c263d6..f5e46afca 100644
--- a/backends/gstreamer/rb-player-gst-helper.c
+++ b/backends/gstreamer/rb-player-gst-helper.c
@@ -426,17 +426,17 @@ rb_gst_create_filter_bin ()
 {
        GstElement *bin;
        GstElement *audioconvert;
-       GstElement *identity;
+       GstElement *volume;
        GstPad *pad;
 
        bin = gst_bin_new ("filterbin");
 
        audioconvert = gst_element_factory_make ("audioconvert", "filteraudioconvert");
-       identity = gst_element_factory_make ("identity", "filteridentity");
-       gst_bin_add_many (GST_BIN (bin), audioconvert, identity, NULL);
-       gst_element_link (identity, audioconvert);
+       volume = gst_element_factory_make ("volume", "filtervolume");
+       gst_bin_add_many (GST_BIN (bin), volume, audioconvert, NULL);
+       gst_element_link (volume, audioconvert);
 
-       pad = gst_element_get_static_pad (identity, "sink");
+       pad = gst_element_get_static_pad (volume, "sink");
        gst_element_add_pad (bin, gst_ghost_pad_new ("sink", pad));
        gst_object_unref (pad);