Hide isXXX() type checking methods in subclasses

Source/core/dom/Document.h

Index: Source/core/dom/Document.h
diff --git a/Source/core/dom/Document.h b/Source/core/dom/Document.h
index d53d3dbf246d877d9428c833585e3309679ed34b..d64d4827c6041ff765885dbd3db3ad9e6ccb061b 100644
--- a/Source/core/dom/Document.h
+++ b/Source/core/dom/Document.h
@@ -1074,6 +1074,10 @@ private:
     friend class Node;
     friend class IgnoreDestructiveWriteCountIncrementer;
 
+    bool isDocumentFragment() const WTF_DELETED_FUNCTION; // Hide to catch useless calls.
+    bool isDocumentNode() const WTF_DELETED_FUNCTION; // Hide to catch useless calls.
+    bool isElementNode() const WTF_DELETED_FUNCTION; // Hide to catch useless calls.
+
     ScriptedAnimationController& ensureScriptedAnimationController();
     virtual SecurityContext& securityContext() OVERRIDE FINAL { return *this; }
     virtual EventQueue* eventQueue() const OVERRIDE FINAL;