[gnome-shell/wip/fmuellner/volume-change-feedback: 58/59] volume: Only emit sound feedback after volume changes

[Jonas Ådahl <jadahl src gnome org>]

commit 5405a16de9cf2241fc7a261f703de550cf3028fa
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Feb 23 23:58:22 2018 +0100

    volume: Only emit sound feedback after volume changes
    
    gnome-settings-daemon doesn't play the volume change sound when
    the volume stayed the same (that is, it is already at its maximum
    or minimum). This looks like the right thing to do, so copy its
    behavior.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/issues/53

 js/ui/status/volume.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/js/ui/status/volume.js b/js/ui/status/volume.js
index 08fb1ccae..68d3804e0 100644
--- a/js/ui/status/volume.js
+++ b/js/ui/status/volume.js
@@ -117,6 +117,7 @@ var StreamSlider = new Lang.Class({
 
         let volume = value * this._control.get_vol_max_norm();
         let prevMuted = this._stream.is_muted;
+        let prevVolume = this._stream.volume;
         if (volume < 1) {
             this._stream.volume = 0;
             if (!prevMuted)
@@ -128,7 +129,8 @@ var StreamSlider = new Lang.Class({
         }
         this._stream.push_volume();
 
-        if (!this._notifyVolumeChangeId && !this._inDrag)
+        let volumeChanged = this._stream.volume != prevVolume;
+        if (volumeChanged && !this._notifyVolumeChangeId && !this._inDrag)
             this._notifyVolumeChangeId = Mainloop.timeout_add(30, () => {
                 this._notifyVolumeChange();
                 this._notifyVolumeChangeId = 0;