WIP - improve ScrollableArea handling.

Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp

Index: Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp
diff --git a/Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp b/Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp
index 35f99757a66f611f8e19cfbbfbef83ce0059d8ff..068c981d701a1968e9927b4465f7177ac82b60b7 100644
--- a/Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp
+++ b/Source/core/layout/compositing/DeprecatedPaintLayerCompositor.cpp
@@ -378,7 +378,7 @@ void DeprecatedPaintLayerCompositor::updateIfNeeded()
         {
             TRACE_EVENT0("blink", "DeprecatedPaintLayerCompositor::updateAfterCompositingChange");
             if (const FrameView::ScrollableAreaSet* scrollableAreas = m_layoutView.frameView()->scrollableAreas()) {
-                for (auto* scrollableArea : *scrollableAreas)
+                for (ScrollableArea* scrollableArea : *scrollableAreas)
                     layersChanged |= scrollableArea->updateAfterCompositingChange();
             }
         }