code: function calcPreferredSize(pw) {
              if (arguments.length > 0) {
                  var bl = [];
                  if (this.$lastWidth < 0 || this.$lastWidth !== pw) {
                      bl = this.$breakToLines(pw);
                  } else {
                      bl = this.$brokenLines;
                  }
  
                  return {
                      width  : pw,
                      height : bl.length * this.getLineHeight() +
                              (bl.length - 1) * this.lineIndent
                  };
              } else {
                  return this.$super();
              }
          }
docs: Get preferred size of the text render
  @param  {Integer} [pw] a width the wrapped text has to be computed
  @return {Object}  a preferred size
  
  { width: {Integer}, height:{Integer} }
  
  @method calcPreferredSize