void HTMLImageFallbackHelper::createAltTextShadowTree(Element& element) {
ShadowRoot& root = element.ensureUserAgentShadowRoot();
HTMLDivElement* container = HTMLDivElement::create(element.document());
root.appendChild(container);
container->setAttribute(idAttr, AtomicString("alttext-container"));
container->setInlineStyleProperty(CSSPropertyOverflow, CSSValueHidden);
container->setInlineStyleProperty(CSSPropertyBorderWidth, 1,
CSSPrimitiveValue::UnitType::Pixels);
container->setInlineStyleProperty(CSSPropertyBorderStyle, CSSValueSolid);
container->setInlineStyleProperty(CSSPropertyBorderColor, CSSValueSilver);
container->setInlineStyleProperty(CSSPropertyDisplay, CSSValueInlineBlock);
container->setInlineStyleProperty(CSSPropertyBoxSizing, CSSValueBorderBox);
container->setInlineStyleProperty(CSSPropertyPadding, 1,
CSSPrimitiveValue::UnitType::Pixels);
HTMLImageElement* brokenImage = HTMLImageElement::create(element.document());
container->appendChild(brokenImage);
brokenImage->setIsFallbackImage();
brokenImage->setAttribute(idAttr, AtomicString("alttext-image"));
brokenImage->setAttribute(widthAttr, AtomicString("16"));
brokenImage->setAttribute(heightAttr, AtomicString("16"));
brokenImage->setAttribute(alignAttr, AtomicString("left"));
brokenImage->setInlineStyleProperty(CSSPropertyMargin, 0,
CSSPrimitiveValue::UnitType::Pixels);
HTMLDivElement* altText = HTMLDivElement::create(element.document());
container->appendChild(altText);
altText->setAttribute(idAttr, AtomicString("alttext"));
altText->setInlineStyleProperty(CSSPropertyOverflow, CSSValueHidden);
altText->setInlineStyleProperty(CSSPropertyDisplay, CSSValueBlock);
Text* text =
Text::create(element.document(), toHTMLElement(element).altText());
altText->appendChild(text);
}
