code: function() {
      var OPERATORS =
          [[Blockly.Msg.CONTROLS_FLOW_STATEMENTS_OPERATOR_BREAK, 'BREAK'],
           [Blockly.Msg.CONTROLS_FLOW_STATEMENTS_OPERATOR_CONTINUE, 'CONTINUE']];
      this.setHelpUrl(Blockly.Msg.CONTROLS_FLOW_STATEMENTS_HELPURL);
      this.setColour(Blockly.Blocks.loops.HUE);
      this.appendDummyInput()
          .appendField(new Blockly.FieldDropdown(OPERATORS), 'FLOW');
      this.setPreviousStatement(true);
      // Assign 'this' to a variable for use in the tooltip closure below.
      var thisBlock = this;
      this.setTooltip(function() {
        var op = thisBlock.getFieldValue('FLOW');
        var TOOLTIPS = {
          'BREAK': Blockly.Msg.CONTROLS_FLOW_STATEMENTS_TOOLTIP_BREAK,
          'CONTINUE': Blockly.Msg.CONTROLS_FLOW_STATEMENTS_TOOLTIP_CONTINUE
        };
        return TOOLTIPS[op];
      });
    }
docs: Block for flow statements: continue, break.
  @this Blockly.Block