code: function(collapsedModel) {
  			if(!this._cursor){
  				return null;
  			}
  			if(this._inParentChain(this._cursor, collapsedModel)){
  				this.setCursor(collapsedModel);
  				return this._cursor;
  			}
  			return null;
  		}
docs: When the parent model containing the cursor is collapsed, the cursor has to be surfaced to the parent