WebViewImpl.prototype.addToThumbnailService = function (
      key, dimensions, callback) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.addToThumbnailService(
      this.guest.getId(), key, dimensions, callback);
};
WebViewImpl.prototype.discardPage = function () {
  if (!this.guest.getId()) {
    return;
  }
  WebViewPrivate.discardPage(this.guest.getId());
};
WebViewImpl.prototype.getPageHistory = function (callback) {
  if (!this.guest.getId()) {
    return;
  }
  WebViewPrivate.getPageHistory(this.guest.getId(), callback);
};
WebViewImpl.prototype.contextMenusCreate = function (createProperties) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.contextMenusCreate(this.guest.getId(), createProperties);
};
WebViewImpl.prototype.setIsFullscreen = function (isFullscreen) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.setIsFullscreen(this.guest.getId(), isFullscreen);
};
WebViewImpl.prototype.getThumbnailFromService = function (callback) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.getThumbnailFromService(this.guest.getId(), callback);
};
WebViewImpl.prototype.showPageInfo = function (pos) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.showPageInfo(this.guest.getId(), pos);
};
WebViewImpl.prototype.setVisible = function (isVisible) {
  if (!this.guest.getId()) {
    return false;
  }
  WebViewPrivate.setVisible(this.guest.getId(), isVisible);
};
WebViewImpl.prototype.isFocusedElementEditable = function (callback) {
  if (!this.guest.getId()) {
    return;
  }
  WebViewPrivate.isFocusedElementEditable(this.guest.getId(), callback);
};