keyring: Don't allow ellipsization of Password label

We don't want the password entry to grow when entering more characters
that fit the available width; as labels' ClutterText ellipsizes by
default, the password label allows the entry to grow by shrinking.
Setting the appropriate ellipsize mode fixes this.

https://bugzilla.gnome.org/show_bug.cgi?id=708324

js/ui/components/keyring.js

@@ -89,6 +89,7 @@ const KeyringDialog = new Lang.Class({
         if (this.prompt.password_visible) {
             let label = new St.Label({ style_class: 'prompt-dialog-password-label' });
             label.set_text(_("Password:"));
+            label.clutter_text.ellipsize = Pango.EllipsizeMode.NONE;
             layout.pack(label, 0, row);
             layout.child_set(label, { x_expand: false, y_fill: false,
                                       x_align: Clutter.TableAlignment.START });