[gnome-shell/wip/carlosg/appdisplay-dnd-rtl] appDisplay: Move onto the correct page while DnD on both LTR/RTL

[Marge Bot <marge-bot src gnome org>]

commit 46361c9a04f4c34f6c510e3dcbc585db81983768
Author: Carlos Garnacho <carlosg gnome org>
Date:   Mon Mar 1 18:13:02 2021 +0100

    appDisplay: Move onto the correct page while DnD on both LTR/RTL
    
    Look up the next page correctly for the overshoot coordinates, given
    the text direction. We don't need to look whether there is a next
    page either, as goToPage() checks that it's the case.
    
    Fixes: https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/3778
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1734>

 js/ui/appDisplay.js | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index dee7df3002..c3958ae9ce 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -475,13 +475,11 @@ var BaseAppView = GObject.registerClass({
         if (this._lastOvershoot >= 0)
             return;
 
-        const currentPosition = this._adjustment.value;
-        const maxPosition = this._adjustment.upper - this._adjustment.page_size;
-
-        if (dragPosition <= gridStart && currentPosition > 0)
-            this.goToPage(this._grid.currentPage - 1);
-        else if (dragPosition >= gridEnd && currentPosition < maxPosition)
-            this.goToPage(this._grid.currentPage + 1);
+        const rtl = this.get_text_direction() === Clutter.TextDirection.RTL;
+        if (dragPosition <= gridStart)
+            this.goToPage(this._grid.currentPage + (rtl ? 1 : -1));
+        else if (dragPosition >= gridEnd)
+            this.goToPage(this._grid.currentPage + (rtl ? -1 : 1));
         else
             return; // don't go beyond first/last page