use setBackgroundMode( NoBackground ) - reduces flickering and doesn't

seem to cause repaint problems

svn path=/trunk/kdebase/kwin/; revision=92918

clients/kstep/nextclient.cpp

@@ -184,6 +184,7 @@ NextButton::NextButton(Client *parent, const char *name,
                        const unsigned char *bitmap, int bw, int bh)
     : QButton(parent, name)
 {
+    setBackgroundMode( NoBackground );
     client = parent;
     resize(18, 18);
 
@@ -218,6 +219,7 @@ NextClient::NextClient( Workspace *ws, WId w, QWidget *parent,
                             const char *name )
     : Client( ws, w, parent, name, WResizeNoErase )
 {
+    setBackgroundMode( NoBackground );
     create_pixmaps();
     connect(options, SIGNAL(resetClients()), this, SLOT(slotReset()));
 

clients/modernsystem/modernsys.cpp

@@ -161,6 +161,7 @@ ModernButton::ModernButton(Client *parent, const char *name,
                            const unsigned char *bitmap)
     : QButton(parent, name)
 {
+    setBackgroundMode( NoBackground );
     QBitmap mask(14, 15, QPixmap::defaultDepth() > 8 ?
                  btnhighcolor_mask_bits : lowcolor_mask_bits, true);
     resize(14, 15);

clients/system/systemclient.cpp

@@ -179,6 +179,7 @@ SystemButton::SystemButton(Client *parent, const char *name,
                            const unsigned char *bitmap)
     : QToolButton(parent, name)
 {
+    setBackgroundMode( NoBackground );
     resize(14, 14);
     connect( this, SIGNAL( clicked() ), this, SLOT( handleClicked() ) );
     if(bitmap)