code: @Test public void testThatFlashCookieClearWorks(){
    Cookie cookie=Cookie.builder("NINJA_FLASH","hello=flashScope").build();
    when(context.getCookie("NINJA_FLASH")).thenReturn(cookie);
    FlashCookie flashCookie=new FlashCookieImpl(ninjaProperties);
    flashCookie.init(context);
    assertEquals("flashScope",flashCookie.get("hello"));
    flashCookie.put("funny new flash message","is there...");
    flashCookie.clearCurrentFlashCookieData();
    assertEquals(0,((FlashCookieImpl)flashCookie).getCurrentFlashCookieData().size());
    assertEquals(1,((FlashCookieImpl)flashCookie).getOutgoingFlashCookieData().size());
  }
  