static void checkIsClippingStackingContextAndContainer(LayoutBoxModelObject& obj)
{
EXPECT_TRUE(obj.canContainFixedPositionObjects());
EXPECT_TRUE(obj.hasClipRelatedProperty());
EXPECT_TRUE(obj.style()->containsPaint());
// TODO(leviw): Ideally, we wouldn't require a paint layer to handle the clipping
// and stacking performed by paint containment.
ASSERT(obj.layer());
PaintLayer* layer = obj.layer();
EXPECT_TRUE(layer->stackingNode() && layer->stackingNode()->isStackingContext());
}
LayerFixedPositionRecorder::LayerFixedPositionRecorder(GraphicsContext& graphicsContext, const LayoutBoxModelObject& layoutObject)
: m_graphicsContext(graphicsContext)
, m_layoutObject(layoutObject)
, m_isFixedPosition(layoutObject.style()->position() == FixedPosition)
, m_isFixedPositionContainer(layoutObject.canContainFixedPositionObjects())
{
if (!RuntimeEnabledFeatures::slimmingPaintCompositorLayerizationEnabled())
return;
if (m_graphicsContext.displayItemList()->displayItemConstructionIsDisabled())
return;
if (m_isFixedPosition)
m_graphicsContext.displayItemList()->createAndAppend<BeginFixedPositionDisplayItem>(m_layoutObject);
// TODO(trchen): Adding a pair of display items on every transformed
// element can be expensive. Investigate whether we can optimize out some
// of them if applicable.
if (m_isFixedPositionContainer)
m_graphicsContext.displayItemList()->createAndAppend<BeginFixedPositionContainerDisplayItem>(m_layoutObject);
}
