Remove CURSOR_VISIBILITY, it's always off

Source/core/rendering/style/RenderStyleConstants.h

Index: Source/core/rendering/style/RenderStyleConstants.h
diff --git a/Source/core/rendering/style/RenderStyleConstants.h b/Source/core/rendering/style/RenderStyleConstants.h
index 052a69c44ddbb0aa7ac7b5fa99df4de263b43a72..eea12ff5b27121de4249def2c99d91fe56e3e623 100644
--- a/Source/core/rendering/style/RenderStyleConstants.h
+++ b/Source/core/rendering/style/RenderStyleConstants.h
@@ -417,13 +417,6 @@ enum ECursor {
     CURSOR_NONE
 };
 
-#if ENABLE(CURSOR_VISIBILITY)
-enum CursorVisibility {
-    CursorVisibilityAuto,
-    CursorVisibilityAutoHide,
-};
-#endif
-
 // The order of this enum must match the order of the display values in CSSValueKeywords.in.
 enum EDisplay {
     INLINE, BLOCK, LIST_ITEM, RUN_IN, COMPACT, INLINE_BLOCK,