Introduce few const getters for dom classes

third_party/WebKit/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 258 matching lines @@
     void setViewportDescription(const ViewportDescription&);
     const ViewportDescription& viewportDescription() const { return m_viewportDescription; }
     Length viewportDefaultMinWidth() const { return m_viewportDefaultMinWidth; }
 
     String outgoingReferrer() const override;
 
     void setDoctype(DocumentType*);
     DocumentType* doctype() const { return m_docType.get(); }
 
     DOMImplementation& implementation();
+    DOMImplementation* maybeImplementation() const;
 
     Element* documentElement() const
     {
         return m_documentElement.get();
     }
 
     // Returns whether the Document has an AppCache manifest.
     bool hasAppCacheManifest() const;
 
     Location* location() const;
@@ skipping 87 matching lines @@
     bool isViewSource() const { return m_isViewSource; }
     void setIsViewSource(bool);
 
     bool sawElementsInKnownNamespaces() const { return m_sawElementsInKnownNamespaces; }
 
     bool isRenderingReady() const { return haveImportsLoaded() && haveStylesheetsLoaded(); }
     bool isScriptExecutionReady() const { return isRenderingReady(); }
 
     // This is a DOM function.
     StyleSheetList* styleSheets();
+    StyleSheetList* maybeStyleSheets() const;
 
     StyleEngine& styleEngine() { DCHECK(m_styleEngine.get()); return *m_styleEngine.get(); }
 
     bool gotoAnchorNeededAfterStylesheetsLoad() { return m_gotoAnchorNeededAfterStylesheetsLoad; }
     void setGotoAnchorNeededAfterStylesheetsLoad(bool b) { m_gotoAnchorNeededAfterStylesheetsLoad = b; }
 
     void scheduleUseShadowTreeUpdate(SVGUseElement&);
     void unscheduleUseShadowTreeUpdate(SVGUseElement&);
 
     // FIXME: SVG filters should change to store the filter on the ComputedStyle
@@ skipping 133 matching lines @@
     KURL completeURLWithOverride(const String&, const KURL& baseURLOverride) const;
     // Determines which base URL should be used given specified override.
     // If override is empty or is about:blank url and parent document exists
     // base URL of parent will be returned, passed base URL override otherwise.
     const KURL& baseURLForOverride(const KURL& baseURLOverride) const;
 
     String userAgent() const final;
     void disableEval(const String& errorMessage) final;
 
     CSSStyleSheet& elementSheet();
+    CSSStyleSheet* maybeElementSheet() const { return m_elemSheet; }
 
     virtual DocumentParser* createParser();
     DocumentParser* parser() const { return m_parser.get(); }
     ScriptableDocumentParser* scriptableDocumentParser() const;
 
     bool printing() const { return m_printing; }
     void setPrinting(bool isPrinting) { m_printing = isPrinting; }
     bool wasPrinting() const { return m_wasPrinting; }
 
     bool paginatedForScreen() const { return m_paginatedForScreen; }
@@ skipping 903 matching lines @@
 DEFINE_TYPE_CASTS(TreeScope, Document, document, true, true);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h