Avoid requiring a recalc to update compositing state for iframes

Source/core/rendering/RenderLayerCompositor.cpp

Index: Source/core/rendering/RenderLayerCompositor.cpp
diff --git a/Source/core/rendering/RenderLayerCompositor.cpp b/Source/core/rendering/RenderLayerCompositor.cpp
index 5b9c0b85a3d3dbeed29555be03ba9475c794c79c..77063e677f3c291aa215bbfc26a5196f87b1b4e0 100644
--- a/Source/core/rendering/RenderLayerCompositor.cpp
+++ b/Source/core/rendering/RenderLayerCompositor.cpp
@@ -2501,6 +2501,7 @@ void RenderLayerCompositor::notifyIFramesOfCompositingChange()
     // Compositing also affects the answer to RenderIFrame::requiresAcceleratedCompositing(), so
     // we need to schedule a style recalc in our parent document.
     if (HTMLFrameOwnerElement* ownerElement = m_renderView->document().ownerElement()) {
+        ownerElement->document().renderView()->compositor()->setNeedsToRecomputeCompositingRequirements();
         DeprecatedScheduleStyleRecalcDuringCompositingUpdate marker(ownerElement->document().lifecycle());
         ownerElement->scheduleLayerUpdate();
     }