code: function TwoWayDiffBlockFeeder(model, mapper, mapperColumnIndex, reverseAnnotation) {
  	    this._mapperColumnIndex = mapperColumnIndex;
  	    this._reverseAnnotation = reverseAnnotation;
  	    this.init(model, mapper);
  	}
docs: Creates a new diff block feeder of one side of the two way compare widget.
  Each item in the feeder is represented by a pair of number [lineIndexOfTheTextModel, correspondingMapperIndex].
  
  @name orion.DiffTreeNavigator.TwoWayDiffBlockFeeder
  @class A feeder to feed all the diff blocks based on the line index and mapper index.
  @param {orion.editor.TextModel} The text model of the whole text.
  @param {array} The mapper generated from the unified diff.
  @param {integer} The column index where the line index can be calculated.
  @param {Boolean} reverseAnnotation Normally the left hand side fo the compare is annotated as geen and the right hand side uses red.
  If this flag is true, we use green annotations on the right and red on the left.