code: function hostClassNamesChanged(oldCassNames, newClassNames) {
                      var currClasses = (newClassNames !== undefined && newClassNames !== null) ? newClassNames.split(_strSpace) : _strEmpty;
                      var oldClasses = (oldCassNames !== undefined && oldCassNames !== null) ? oldCassNames.split(_strSpace) : _strEmpty;
                      if (currClasses === _strEmpty && oldClasses === _strEmpty)
                          return false;
                      var diff = getArrayDifferences(oldClasses, currClasses);
                      var changed = false;
                      var oldClassNames = _oldClassName !== undefined && _oldClassName !== null ? _oldClassName.split(_strSpace) : [_strEmpty];
                      var currClassNames = _classNameCache !== undefined && _classNameCache !== null ? _classNameCache.split(_strSpace) : [_strEmpty];
  
                      //remove none theme from diff list to prevent update
                      var idx = FRAMEWORK.inArray(_classNameThemeNone, diff);
                      var curr;
                      var i;
                      var v;
                      var o;
                      var c;
  
                      if (idx > -1)
                          diff.splice(idx, 1);
  
                      for (i = 0; i < diff.length; i++) {
                          curr = diff[i];
                          if (curr.indexOf(_classNameHostElement) !== 0) {
                              o = true;
                              c = true;
                              for (v = 0; v < oldClassNames.length; v++) {
                                  if (curr === oldClassNames[v]) {
                                      o = false;
                                      break;
                                  }
                              }
                              for (v = 0; v < currClassNames.length; v++) {
                                  if (curr === currClassNames[v]) {
                                      c = false;
                                      break;
                                  }
                              }
                              if (o && c) {
                                  changed = true;
                                  break;
                              }
                          }
  
                      }
                      return changed;
                  }
docs: Returns true if the class names really changed (new class without plugin host prefix)
  @param oldCassNames The old ClassName string.
  @param newClassNames The new ClassName string.
  @returns {boolean} True if the class names has really changed, false otherwise.