public void TestExsFontSize()
    {
        CssCollectedStyleDeclaration csd = new CssCollectedStyleDeclaration(getElm());

        csd.CollectProperty("font-size", 1, CssValue.GetCssValue("2ex", false), CssStyleSheetType.Author, "");

        CssPrimitiveValue cssPrimValue = csd.GetPropertyCssValue("font-size") as CssPrimitiveValue;

        Assert.AreEqual(10, cssPrimValue.GetFloatValue(CssPrimitiveType.Px));
    }
    public void TestEmsNotFontSize()
    {
        CssCollectedStyleDeclaration csd = new CssCollectedStyleDeclaration(getElm());

        csd.CollectProperty("notFontSize", 1, CssValue.GetCssValue("2em", false), CssStyleSheetType.Author, "");

        CssPrimitiveValue cssPrimValue = csd.GetPropertyCssValue("notFontSize") as CssPrimitiveValue;

        Assert.AreEqual(typeof(CssAbsPrimitiveLengthValue), cssPrimValue.GetType());
        Assert.AreEqual(20, cssPrimValue.GetFloatValue(CssPrimitiveType.Px));
    }