Have positionInParentBeforeNode() / positionInParentAfterNode() take a reference

Source/core/editing/VisibleUnits.cpp

Index: Source/core/editing/VisibleUnits.cpp
diff --git a/Source/core/editing/VisibleUnits.cpp b/Source/core/editing/VisibleUnits.cpp
index 8214b42adfb3e9bfbbf0b42e3721e9bc5bba7bcf..723a7c3e4acdb54e0924fd81f80c9d1b2d148f7e 100644
--- a/Source/core/editing/VisibleUnits.cpp
+++ b/Source/core/editing/VisibleUnits.cpp
@@ -952,7 +952,7 @@ VisiblePosition previousLinePosition(const VisiblePosition &visiblePosition, int
         RenderObject& renderer = root->closestLeafChildForPoint(pointInLine, isEditablePosition(p))->renderer();
         Node* node = renderer.node();
         if (node && editingIgnoresContent(node))
-            return VisiblePosition(positionInParentBeforeNode(node));
+            return VisiblePosition(positionInParentBeforeNode(*node));
         return VisiblePosition(renderer.positionForPoint(pointInLine));
     }
 
@@ -1010,7 +1010,7 @@ VisiblePosition nextLinePosition(const VisiblePosition &visiblePosition, int lin
         RenderObject& renderer = root->closestLeafChildForPoint(pointInLine, isEditablePosition(p))->renderer();
         Node* node = renderer.node();
         if (node && editingIgnoresContent(node))
-            return VisiblePosition(positionInParentBeforeNode(node));
+            return VisiblePosition(positionInParentBeforeNode(*node));
         return VisiblePosition(renderer.positionForPoint(pointInLine));
     }