Use enclosingIntRect instead of pixelSnappedIntRect to expand invalidation.

Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp

Index: Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp
diff --git a/Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp b/Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp
index 422c49504f6943e63b12d75b62910100a9d5d901..6d56b078c9263b881ba7e4af5028bffadbf97538 100644
--- a/Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp
+++ b/Source/core/layout/compositing/CompositedDeprecatedPaintLayerMapping.cpp
@@ -2039,7 +2039,7 @@ void CompositedDeprecatedPaintLayerMapping::setContentsNeedDisplayInRect(const L
     // FIXME: need to split out paint invalidations for the background.
     // FIXME: need to distinguish invalidations for different layers (e.g. the main layer and scrolling layer). crbug.com/416535.
     SetContentsNeedsDisplayInRectFunctor functor = {
-        pixelSnappedIntRect(r.location() + m_owningLayer.subpixelAccumulation(), r.size()),
+        enclosingIntRect(LayoutRect(r.location() + m_owningLayer.subpixelAccumulation(), r.size())),
         invalidationReason
     };
     ApplyToGraphicsLayers(this, functor, ApplyToContentLayers);