Clarify comments for methods added in r178921

Source/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 1055 matching lines @@
 
     virtual PassRefPtrWillBeRawPtr<Document> cloneDocumentWithoutChildren();
 
     bool importContainerNodeChildren(ContainerNode* oldContainerNode, PassRefPtrWillBeRawPtr<ContainerNode> newContainerNode, ExceptionState&);
     void lockCompatibilityMode() { m_compatibilityModeLocked = true; }
 
 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.
+    bool isDocumentFragment() const WTF_DELETED_FUNCTION; // This will catch anyone doing an unnecessary check.
+    bool isDocumentNode() const WTF_DELETED_FUNCTION; // This will catch anyone doing an unnecessary check.
+    bool isElementNode() const WTF_DELETED_FUNCTION; // This will catch anyone doing an unnecessary check.
 
     ScriptedAnimationController& ensureScriptedAnimationController();
     virtual SecurityContext& securityContext() OVERRIDE FINAL { return *this; }
     virtual EventQueue* eventQueue() const OVERRIDE FINAL;
 
     // FIXME: Rename the StyleRecalc state to RenderTreeUpdate.
     bool hasPendingStyleRecalc() const { return m_lifecycle.state() == DocumentLifecycle::VisualUpdatePending; }
 
     bool shouldScheduleRenderTreeUpdate() const;
     void scheduleRenderTreeUpdate();
@@ skipping 343 matching lines @@
 Node* eventTargetNodeForDocument(Document*);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h