code: function() {
              if (!this.isTextArea) {
                  return false;
              }
  
              var inputEl = this.textField.inputEl;
              var overflowY = inputEl.getStyle('overflow-y');
              if (overflowY == 'hidden' || overflowY == 'visible') {
                  return false;
              }
              if (overflowY == 'scroll') {
                  return true;
              }
              //noinspection RedundantIfStatementJS
              if (inputEl.dom.scrollHeight <= inputEl.dom.clientHeight) {
                  return false;
              }
              return true;
          }
docs: Checks if the field we are attached to currently has a scrollbar