title: Issue with fitInView of QGraphicsView when ItemIgnoresTransformations is on
body: <p>While trying to implement a scene where item sizes do not change but distances between items get magnified I encountered this problem with the following code which draws a rectangle and the text "A". Now if I set the flag ItemIgnoresTransformations on the rectangle item, zooming in causes the rectangle to vanish (click and drag mouse button around the rectangle). But that does not happen in case of the text. Also, the new viewport area set by fitInView is very different for I asked for:</p>
  
  <pre class="lang-py prettyprint-override"><code>import sys
  from PyQt4 import QtCore, QtGui
  
  class GV(QtGui.QGraphicsView):
      def __init__(self, *args, **kwargs):
          QtGui.QGraphicsView.__init__(self, *args, **kwargs)
  
      def mousePressEvent(self, event):
          pos = QtCore.QPoint(event.pos())
          self.startPos = pos
  
      def mouseReleaseEvent(self, event):
          pos = QtCore.QPoint(event.pos())
          self.endPos = pos
          rect = QtCore.QRect(self.startPos, self.endPos) 
          sceneRect = self.mapToScene(rect).boundingRect()
          print 'Selected area: viewport coordinate:', rect, \
              ', scene coordinate:', sceneRect
          self.fitInView(sceneRect)
          print 'new viewport in scene coordinates:', \
              self.mapToScene(self.viewport().geometry()).boundingRect()
  
  class Scene(QtGui.QGraphicsScene):
      def __init__(self, *args, **kwargs):
          QtGui.QGraphicsScene.__init__(self, *args, **kwargs)    
          self.itemA = QtGui.QGraphicsSimpleTextItem('A')
          self.itemA.setPos(20, 20)
          self.itemA.setFlag(QtGui.QGraphicsItem.ItemIgnoresTransformations, True)
          self.addItem(self.itemA)
          self.itemB = QtGui.QGraphicsRectItem(30, 50, 20, 20)
          self.addItem(self.itemB)
          self.itemB.setFlag(QtGui.QGraphicsItem.ItemIgnoresTransformations, True)
  
  if __name__ == '__main__':
      app = QtGui.QApplication(sys.argv)
      widget = QtGui.QMainWindow()
      scene = Scene()
      view = GV(scene, widget)
      widget.setCentralWidget(view)
      widget.show()
      app.exec_()
  </code></pre>
  
  <p>Any explanations will be appreciated!</p>