cleanup: Remove some unhelpful unused arguments

Those unused arguments aren't bugs - unbeknownst to eslint, they all
correspond to valid signal parameters - but they don't contribute
anything to clarity, so just remove them anyway.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/627

js/ui/workspace.js

@@ -376,7 +376,7 @@ var WindowClone = GObject.registerClass({
         return false;
     }
 
-    _onClicked(action, actor) {
+    _onClicked() {
         this._activate();
     }
 
@@ -467,7 +467,7 @@ var WindowOverlay = class {
 
         this._maxTitleWidth = -1;
 
-        this._updateCaptionId = metaWindow.connect('notify::title', w => {
+        this._updateCaptionId = metaWindow.connect('notify::title', () => {
             this.title.text = this._getCaption();
             this.relayout(false);
         });