apps-menu: Remove vertical separator

Ever since gnome-shell stopped using a stippled separator in the
calendar menu, the styling required by the separator has been
missing.

There haven't been any complaints about the invisible separator,
so we can just as well drop it altogether.

Part-of:
<https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/290>
(cherry picked from commit c3cbef19ac)

extensions/apps-menu/extension.js

@@ -432,15 +432,6 @@ class ApplicationsButton extends PanelMenu.Button {
         }
     }
 
-    _createVertSeparator() {
-        let separator = new St.DrawingArea({
-            style_class: 'calendar-vertical-separator',
-            pseudo_class: 'highlighted',
-        });
-        separator.connect('repaint', this._onVertSepRepaint.bind(this));
-        return separator;
-    }
-
     _onDestroy() {
         super._onDestroy();
 
@@ -462,21 +453,6 @@ class ApplicationsButton extends PanelMenu.Button {
         return super._onMenuKeyPress(actor, event);
     }
 
-    _onVertSepRepaint(area) {
-        let cr = area.get_context();
-        let themeNode = area.get_theme_node();
-        let [width, height] = area.get_surface_size();
-        let stippleColor = themeNode.get_color('-stipple-color');
-        let stippleWidth = themeNode.get_length('-stipple-width');
-        let x = Math.floor(width / 2) + 0.5;
-        cr.moveTo(x, 0);
-        cr.lineTo(x, height);
-        Clutter.cairo_set_source_color(cr, stippleColor);
-        cr.setDash([1, 3], 1); // Hard-code for now
-        cr.setLineWidth(stippleWidth);
-        cr.stroke();
-    }
-
     _onOpenStateChanged(menu, open) {
         if (open) {
             if (this.reloadFlag) {
@@ -583,7 +559,6 @@ class ApplicationsButton extends PanelMenu.Button {
         this.categoriesScrollBox.add_actor(this.categoriesBox);
 
         this.mainBox.add(this.leftBox);
-        this.mainBox.add_child(this._createVertSeparator());
         this.mainBox.add_child(this.applicationsScrollBox);
         section.actor.add_actor(this.mainBox);
     }