Mark when we may have been invalidated to early out on repaintTreeAfterLayout.

Source/core/rendering/RenderBlockFlow.cpp

Index: Source/core/rendering/RenderBlockFlow.cpp
diff --git a/Source/core/rendering/RenderBlockFlow.cpp b/Source/core/rendering/RenderBlockFlow.cpp
index 8e0b0e212ea6853508531de0777fdd7f092e133b..82bfbb083a238cda8e905a129f6337268015d038 100644
--- a/Source/core/rendering/RenderBlockFlow.cpp
+++ b/Source/core/rendering/RenderBlockFlow.cpp
@@ -906,6 +906,8 @@ void RenderBlockFlow::layoutBlockChildren(bool relayoutChildren, SubtreeLayoutSc
 
         updateBlockChildDirtyBitsBeforeLayout(relayoutChildren, child);
 
+        child->setMayNeedInvalidation(true);
+
         if (child->isOutOfFlowPositioned()) {
             child->containingBlock()->insertPositionedObject(child);
             adjustPositionedBlock(child, marginInfo);
@@ -2315,6 +2317,7 @@ bool RenderBlockFlow::positionNewFloats()
             continue;
 
         RenderBox* childBox = floatingObject->renderer();
+        childBox->setMayNeedInvalidation(true);
 
         LayoutUnit childLogicalLeftMargin = style()->isLeftToRightDirection() ? marginStartForChild(childBox) : marginEndForChild(childBox);
         LayoutRect oldRect = childBox->frameRect();