QtWidgets: cleanup several Q3* items

Change-Id: I0812cdd74f19b4c98336724ea722807d4c68cf7d
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

src/widgets/kernel/qwidget.cpp

@@ -2708,7 +2708,7 @@ Qt::WindowStates QWidget::windowState() const
    The function sets the window state on child widgets similar to
    setWindowState(). The difference is that the window state changed
    event has the isOverride() flag set. It exists mainly to keep
-   Q3Workspace working.
+   QWorkspace working.
  */
 void QWidget::overrideWindowState(Qt::WindowStates newstate)
 {

src/widgets/widgets/qframe.cpp

@@ -486,7 +486,7 @@ void QFrame::paintEvent(QPaintEvent *)
 /*!
     \internal
 
-    Mostly for the sake of Q3Frame
+    Used by QLabel and QLCDNumber
  */
 void QFrame::drawFrame(QPainter *p)
 {

src/widgets/widgets/qmenubar_p.h

@@ -53,7 +53,6 @@
 // We mean it.
 //
 
-#ifndef QMAC_Q3MENUBAR_CPP_FILE
 #include "QtWidgets/qstyleoption.h"
 #include <private/qmenu_p.h> // Mac needs what in this file!
 
@@ -190,7 +189,6 @@ public:
     QAction *menuBarAction;
 #endif
 };
-#endif
 
 #endif // QT_NO_MENUBAR