[LyX/2.1.x] Fix setting of pref "hide scrollbar in fullscreen"

[Scott Kostyshak]

commit 1b596e929f407096ed15e1f2e9af95384ac16753
Author: Scott Kostyshak <skost...@lyx.org>
Date:   Thu Jun 25 08:21:46 2015 -0400

    Fix setting of pref "hide scrollbar in fullscreen"
    
    The symptom of the bug is that the preference could be incorrectly
    displayed (based on the value of the statusbar preference).
    
    This seems to have been a copy/paste mistake introduced in 214f7ed2.
    
    (cherry picked from commit 5e7cbc8f2c141889950628d0b81fcdb148fa278b)

diff --git a/src/frontends/qt4/GuiPrefs.cpp b/src/frontends/qt4/GuiPrefs.cpp
index 92885c5..ae5d336 100644
--- a/src/frontends/qt4/GuiPrefs.cpp
+++ b/src/frontends/qt4/GuiPrefs.cpp
@@ -2764,7 +2764,7 @@ void PrefEdit::update(LyXRC const & rc)
        macroEditStyleCO->setCurrentIndex(rc.macro_edit_style);
        cursorWidthSB->setValue(rc.cursor_width);
        toggleScrollbarCB->setChecked(rc.full_screen_scrollbar);
-       toggleScrollbarCB->setChecked(rc.full_screen_statusbar);
+       toggleStatusbarCB->setChecked(rc.full_screen_statusbar);
        toggleToolbarsCB->setChecked(rc.full_screen_toolbars);
        toggleTabbarCB->setChecked(rc.full_screen_tabbar);
        toggleMenubarCB->setChecked(rc.full_screen_menubar);