fix related to #3100 and missed in r15474

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@15512 c8812cc2-4d05-0410-92ff-de0c093fc19c

python/plugins/GdalTools/tools/doContour.py

@@ -32,8 +32,7 @@ def __init__(self, iface):
       self.connect(self.selectInputFileButton, SIGNAL("clicked()"), self.fillInputFileEdit)
       self.connect(self.selectOutputDirButton, SIGNAL("clicked()"), self.fillOutputDirEdit)
 
-      # fill layers combo
-      self.connect(Utils.LayerRegistry.instance(), SIGNAL("layersChanged"), self.fillInputLayerCombo)
+  def onLayersChanged(self):
       self.fillInputLayerCombo()
 
   def fillInputLayerCombo( self ):