system: Use username if full name is longer than 100 characters

The current code relies on unstable behavior of ClutterText, and
does not really work as expected. Still, limiting the label size
is important.

Use a hardcoded limit of 100 characters instead of checking if
the layout is ellipsized already.

js/ui/status/system.js

@@ -4,6 +4,7 @@ const AccountsService = imports.gi.AccountsService;
 const Clutter = imports.gi.Clutter;
 const Gio = imports.gi.Gio;
 const GLib = imports.gi.GLib;
+const Pango = imports.gi.Pango;
 const Shell = imports.gi.Shell;
 const St = imports.gi.St;
 const GObject = imports.gi.GObject;
@@ -163,18 +164,15 @@ var Indicator = class extends PanelMenu.SystemIndicator {
     }
 
     _updateSwitchUserSubMenu() {
-        this._switchUserSubMenu.label.text = this._user.get_real_name();
-        let clutterText = this._switchUserSubMenu.label.clutter_text;
+        let realName = this._user.get_real_name();
 
-        // XXX -- for some reason, the ClutterText's width changes
-        // rapidly unless we force a relayout of the actor. Probably
-        // a size cache issue or something. Moving this to be a layout
-        // manager would be a much better idea.
-        clutterText.get_allocation_box();
-
-        let layout = clutterText.get_layout();
-        if (layout.is_ellipsized())
+        // In theory, GNOME allows creating users with names up to 255
+        // characters, but such long names look terribly bad, so limit
+        // to 100 and it should fit the vast majority of screen sizes.
+        if (realName.length > 100)
             this._switchUserSubMenu.label.text = this._user.get_user_name();
+        else
+            this._switchUserSubMenu.label.text = realName;
 
         let iconFile = this._user.get_icon_file();
         if (iconFile && !GLib.file_test(iconFile, GLib.FileTest.EXISTS))
@@ -211,6 +209,7 @@ var Indicator = class extends PanelMenu.SystemIndicator {
 
         this._switchUserSubMenu = new PopupMenu.PopupSubMenuMenuItem('', true);
         this._switchUserSubMenu.icon.style_class = 'system-switch-user-submenu-icon';
+        this._switchUserSubMenu.label.clutter_text.ellipsize = Pango.EllipsizeMode.END;
 
         // Since the label of the switch user submenu depends on the width of
         // the popup menu, and we can't easily connect on allocation-changed

js/ui/userWidget.js

@@ -7,6 +7,7 @@ const AccountsService = imports.gi.AccountsService;
 const GLib = imports.gi.GLib;
 const Gio = imports.gi.Gio;
 const GObject = imports.gi.GObject;
+const Pango = imports.gi.Pango;
 const St = imports.gi.St;
 
 const Params = imports.misc.params;
@@ -72,6 +73,7 @@ class UserWidgetLabel extends St.Widget {
 
         this._realNameLabel = new St.Label({ style_class: 'user-widget-label',
                                              y_align: Clutter.ActorAlign.CENTER });
+        this._realNameLabel.clutter_text.ellipsize = Pango.EllipsizeMode.END;
         this.add_child(this._realNameLabel);
 
         this._userNameLabel = new St.Label({ style_class: 'user-widget-label',