Plumb selection bounds as a single unit

Source/core/layout/compositing/CompositedSelectionBound.h

Index: Source/core/layout/compositing/CompositedSelectionBound.h
diff --git a/Source/core/layout/compositing/CompositedSelectionBound.h b/Source/core/layout/compositing/CompositedSelectionBound.h
index d9cc88a412fa983f32f4f8a587f8d281ceafb718..10d25af08ef0edc55256eef4c37301dcf4859672 100644
--- a/Source/core/layout/compositing/CompositedSelectionBound.h
+++ b/Source/core/layout/compositing/CompositedSelectionBound.h
@@ -37,26 +37,20 @@
 namespace blink {
 
 struct CompositedSelectionBound {
-    enum Type {
-        Caret,
-        SelectionLeft,
-        SelectionRight
-    };
-
     CompositedSelectionBound()
-        : type(Caret)
-        , layer(nullptr)
+        : layer(nullptr)
+        , isTextDirectionRTL(false)
     {
     }
 
-    Type type;
-
     // The structure describes the position of a caret in space of the GraphicsLayer the caret resides in.
     // Where edgeTopInLayer is the top point of the caret, usually on the ascend line of the line box,
     // and edgeBottomInLayer it the bottom point, on the baseline of the line box.
     GraphicsLayer* layer;
     FloatPoint edgeTopInLayer;
     FloatPoint edgeBottomInLayer;
+
+    bool isTextDirectionRTL;
 };
 
 } // namespace blink