Qt, Sprefs: hide the style selection on Win32 and fix it

modules/gui/qt4/components/simple_preferences.cpp

@@ -543,7 +543,7 @@ SPrefsPanel::SPrefsPanel( intf_thread_t *_p_intf, QWidget *_parent,
 
             optionWidgets.append( ui.skins );
             optionWidgets.append( ui.qt4 );
-#if !defined(NDEBUG) || !defined( WIN32)
+#if !defined( WIN32)
             ui.stylesCombo->addItem( qtr("System's default") );
             ui.stylesCombo->addItems( QStyleFactory::keys() );
             ui.stylesCombo->setCurrentIndex( ui.stylesCombo->findText(
@@ -556,6 +556,7 @@ SPrefsPanel::SPrefsPanel( intf_thread_t *_p_intf, QWidget *_parent,
             optionWidgets.append( ui.stylesCombo );
 #else
             ui.stylesCombo->hide();
+            ui.stylesLabel->hide();
             optionWidgets.append( NULL );
 #endif
             radioGroup = new QButtonGroup(this);

modules/gui/qt4/ui/sprefs_interface.ui

@@ -495,7 +495,7 @@
               </widget>
              </item>
              <item row="5" column="0">
-              <widget class="QLabel" name="label">
+              <widget class="QLabel" name="stylesLabel">
                <property name="sizePolicy">
                 <sizepolicy hsizetype="Maximum" vsizetype="Preferred">
                  <horstretch>0</horstretch>