overviewControls: Use correct translation in dragBegin

Commit 12845f0eefa reset translationX to 0 to fix the slide-in
animation of the dash when dragging a search result, but 0 is the
wrong value for the thumbnail slider - the next time it will be
shown, it will just pop up instead of sliding in due to translationX
already being at its target value.
Fix this by making _updateTranslation take the actual visibility into
account and call that to set the correct translation in dragBegin.

diff --git a/js/ui/overviewControls.js b/js/ui/overviewControls.js
index 4bd3d67abc32ea193945620d424c1e9584bfc21b..02423f2d8949edb212078b899a0e377432e21488 100644 (file)
--- a/js/ui/overviewControls.js
+++ b/js/ui/overviewControls.js
@@ -161,7 +161,8 @@ const SlidingControl = new Lang.Class({
         let translationEnd = 0;
         let translation = this._getTranslation();
 
-        if (this._visible) {
+        let shouldShow = (this._getSlide() > 0);
+        if (shouldShow) {
             translationStart = translation;
         } else {
             translationEnd = translation;
@@ -192,7 +193,7 @@ const SlidingControl = new Lang.Class({
 
     _onDragBegin: function() {
         this._inDrag = true;
-        this.layout.translationX = 0;
+        this._updateTranslation();
         this._updateSlide();
     },