workspace: Don't initially hide the title of window overlays

To be able to read the properties of the title correctly during the
first relayout of the overlay, the title, just like the border, can't be
hidden. Otherwise the title can be misaligned some pixels to the left
sometimes.

This slighty worsens the issue that windows moved to a separate
workspace using DND will show an overlay when the workspace is shown in
the overview even though no window is pointed at. Before this commit,
only the border would be visible for windows moved to another workspace,
now the title also is.

js/ui/workspace.js

@@ -470,7 +470,6 @@ var WindowOverlay = new Lang.Class({
         this._windowAddedId = 0;
 
         button.hide();
-        title.hide();
 
         this.title = title;
         this.closeButton = button;