Center-align all menus

Make popup menus center-aligned on their parent buttons, to
match the default GNOME Shell panel menus. Affects:
- Places menu
- Drive menu
- Workspace indicator
- Window menu workspace indicator

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/246>

extensions/drive-menu/extension.js

@@ -142,7 +142,7 @@ class DriveMenu extends PanelMenu.Button {
     }
 
     constructor() {
-        super(0.0, _('Removable devices'));
+        super(0.5, _('Removable devices'));
 
         let icon = new St.Icon({
             icon_name: 'media-eject-symbolic',

extensions/places-menu/extension.js

@@ -91,7 +91,7 @@ class PlacesMenu extends PanelMenu.Button {
     }
 
     constructor() {
-        super(0.0, _('Places'));
+        super(0.5, _('Places'));
 
         let label = new St.Label({
             text: _('Places'),

extensions/window-list/workspaceIndicator.js

@@ -258,7 +258,7 @@ var WorkspaceIndicator = class WorkspaceIndicator extends PanelMenu.Button {
     }
 
     constructor() {
-        super(0.0, _('Workspace Indicator'), true);
+        super(0.5, _('Workspace Indicator'), true);
         this.setMenu(new PopupMenu.PopupMenu(this, 0.0, St.Side.BOTTOM));
         this.add_style_class_name('window-list-workspace-indicator');
         this.remove_style_class_name('panel-button');

extensions/workspace-indicator/extension.js

@@ -263,7 +263,7 @@ class WorkspaceIndicator extends PanelMenu.Button {
     }
 
     constructor() {
-        super(0.0, _('Workspace Indicator'));
+        super(0.5, _('Workspace Indicator'));
 
         let container = new St.Widget({
             layout_manager: new Clutter.BinLayout(),