How to use the keycode.isEventKey function in keycode

handleKeyDown(event) {

    // Escape or Tab unpress the 'button'
    if (keycode.isEventKey(event, 'Esc') || keycode.isEventKey(event, 'Tab')) {
      if (this.buttonPressed_) {
        this.unpressButton();
      }

      // Don't preventDefault for Tab key - we still want to lose focus
      if (!keycode.isEventKey(event, 'Tab')) {
        event.preventDefault();
        // Set focus back to the menu button's button
        this.menuButton_.focus();
      }
    // Up Arrow or Down Arrow also 'press' the button to open the menu
    } else if (keycode.isEventKey(event, 'Up') || keycode.isEventKey(event, 'Down')) {
      if (!this.buttonPressed_) {
        event.preventDefault();
        this.pressButton();
      }

handleSubmenuKeyDown(event) {
    // Escape or Tab unpress the 'button'
    if (keycode.isEventKey(event, 'Esc') || keycode.isEventKey(event, 'Tab')) {
      if (this.buttonPressed_) {
        this.unpressButton();
      }
      // Don't preventDefault for Tab key - we still want to lose focus
      if (!keycode.isEventKey(event, 'Tab')) {
        event.preventDefault();
        // Set focus back to the menu button's button
        this.menuButton_.focus();
      }
    } else {
      // NOTE: This is a special case where we don't pass unhandled
      //  keydown events up to the Component handler, because it is
      //  just entending the keydown handling of the `MenuItem`
      //  in the `Menu` which already passes unused keys up.
    }
  }

handleKeyDown(event) {

    // Escape or Tab unpress the 'button'
    if (keycode.isEventKey(event, 'Esc') || keycode.isEventKey(event, 'Tab')) {
      if (this.buttonPressed_) {
        this.unpressButton();
      }

      // Don't preventDefault for Tab key - we still want to lose focus
      if (!keycode.isEventKey(event, 'Tab')) {
        event.preventDefault();
        // Set focus back to the menu button's button
        this.menuButton_.focus();
      }
    // Up Arrow or Down Arrow also 'press' the button to open the menu
    } else if (keycode.isEventKey(event, 'Up') || keycode.isEventKey(event, 'Down')) {
      if (!this.buttonPressed_) {
        event.preventDefault();
        this.pressButton();
      }
    }
  }

handleKeyDown(event) {

    // Ignore Space or Enter key operation, which is handled by the browser for
    // a button - though not for its super class, ClickableComponent. Also,
    // prevent the event from propagating through the DOM and triggering Player
    // hotkeys. We do not preventDefault here because we _want_ the browser to
    // handle it.
    if (keycode.isEventKey(event, 'Space') || keycode.isEventKey(event, 'Enter')) {
      event.stopPropagation();
      return;
    }

    // Pass keypress handling up for unsupported keys
    super.handleKeyDown(event);
  }
}

handleKeyDown(event) {

    // Left and Down Arrows
    if (keycode.isEventKey(event, 'Left') || keycode.isEventKey(event, 'Down')) {
      event.preventDefault();
      event.stopPropagation();
      this.stepBack();

    // Up and Right Arrows
    } else if (keycode.isEventKey(event, 'Right') || keycode.isEventKey(event, 'Up')) {
      event.preventDefault();
      event.stopPropagation();
      this.stepForward();
    } else {

      // Pass keydown handling up for unsupported keys
      super.handleKeyDown(event);
    }
  }

handleKeyDown(event) {

    // Left and Down Arrows
    if (keycode.isEventKey(event, 'Left') || keycode.isEventKey(event, 'Down')) {
      event.preventDefault();
      event.stopPropagation();
      this.stepForward();

    // Up and Right Arrows
    } else if (keycode.isEventKey(event, 'Right') || keycode.isEventKey(event, 'Up')) {
      event.preventDefault();
      event.stopPropagation();
      this.stepBack();
    }
  }

it('should allow to compare events to their keyCodes)', function() {
    var event = { which: 13, keyCode: 13, charCode: 13 };
    assert.strictEqual(keycode.isEventKey(event, 13), true);
    assert.strictEqual(keycode.isEventKey(event, 14), false);
  });

handleKeyDown(event) {
    if (keycode.isEventKey(event, 'Space') || keycode.isEventKey(event, 'Enter')) {
      event.preventDefault();
      event.stopPropagation();
      this.handleAction(event);
    } else if (keycode.isEventKey(event, 'Home')) {
      event.preventDefault();
      event.stopPropagation();
      this.player_.currentTime(0);
    } else if (keycode.isEventKey(event, 'End')) {
      event.preventDefault();
      event.stopPropagation();
      this.player_.currentTime(this.player_.duration());
    } else if (/^[0-9]$/.test(keycode(event))) {
      event.preventDefault();
      event.stopPropagation();
      const gotoFraction = (keycode.codes[keycode(event)] - keycode.codes['0']) * 10.0 / 100.0;

      this.player_.currentTime(this.player_.duration() * gotoFraction);
    } else if (keycode.isEventKey(event, 'PgDn')) {
      event.preventDefault();
      event.stopPropagation();

handleKeyPress(event) {
    if (keycode.isEventKey(event, 'Esc')) {
      this.handleMouseOut();
    }
  }
}