viewSelector: Allow to close the application view with escape

With the latest changes to the overview, the application view is now
clearly on a different level compared to the window picker. For that
reason it now makes sense to close it on Escape rather than hiding
the overview directly, as we do for search.

https://bugzilla.gnome.org/show_bug.cgi?id=682109

js/ui/viewSelector.js

@@ -240,6 +240,8 @@ const ViewSelector = new Lang.Class({
         if (symbol == Clutter.Escape) {
             if (this.active)
                 this.reset();
+            else if (this._showAppsButton.checked)
+                this._resetShowAppsButton();
             else
                 Main.overview.hide();
             return true;