QTreeView does not account for the height of the columns outside of the viewport

QTreeView does not account for the height of the columns
that are outside of the viewport when calculating the height of an item.

This leads to a corrupted display as the example in attachment shows.

Both items should have height of at least 128 pixels, which is the size
of the pixmap inserted in the first column. But since the first column
isn't actually in the viewport then the height is incorrectly computed
as the height of the text present in the visible columns.

If the first column is in the viewport when the widget shows up then the items
have the correct height.

If the pixmap is inserted in a column that is far on the right and
the view isn't scrolled then the problem doesn't show up even if
the pixmap is outside of the view. This suggests that the bug
affects only the left side of an item.

A common example is when items are added at runtime and the user has scrolled the view manually.

#include <QtGui>

int main(int argc,char ** argv)
{
QApplication app(argc,argv);

QTreeWidget * tw = new QTreeWidget( 0 );
tw->setAllColumnsShowFocus( true );
tw->setExpandsOnDoubleClick( true );

QStringList headerLabels;
headerLabels.append( "COLUMN 1" );
headerLabels.append( "COLUMN 2" );
headerLabels.append( "COLUMN 3" );
headerLabels.append( "COLUMN 4" );
headerLabels.append( "COLUMN 5" );
headerLabels.append( "COLUMN 6" );
headerLabels.append( "COLUMN 7" );
headerLabels.append( "COLUMN 8" );
tw->setHeaderLabels( headerLabels );

QPixmap pix( 128,128 );
pix.fill( QColor( 255,0,0 ) );

QTreeWidgetItem * par = new QTreeWidgetItem( tw );
par->setIcon( 0, pix );
par->setText( 0, "PARENT COLUMN 1" );
par->setText( 1, "PARENT COLUMN 2" );
par->setText( 2, "PARENT COLUMN 3" );
par->setText( 3, "PARENT COLUMN 4" );
par->setText( 4, "PARENT COLUMN 5" );
par->setText( 5, "PARENT COLUMN 6" );
par->setText( 6, "PARENT COLUMN 7" );
par->setText( 7, "PARENT COLUMN 8" );

QTreeWidgetItem * item = new QTreeWidgetItem( par );
item->setIcon( 0, pix );
item->setText( 0, "CHILD COLUMN 1" );
item->setText( 1, "CHILD COLUMN 2" );

//mt->runAllTests();

tw->setIconSize( QSize( 128, 128 ) );
tw->show();

tw->horizontalScrollBar()->setValue( 500 );
par->setExpanded( true );

return app.exec();
}