Remove CSS_REGIONS compile flag from Blink.

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 291 matching lines @@
     PassRefPtr<ProcessingInstruction> createProcessingInstruction(const String& target, const String& data, ExceptionCode&);
     PassRefPtr<Attr> createAttribute(const String& name, ExceptionCode&);
     PassRefPtr<Attr> createAttributeNS(const String& namespaceURI, const String& qualifiedName, ExceptionCode&, bool shouldIgnoreNamespaceChecks = false);
     PassRefPtr<EntityReference> createEntityReference(const String& name, ExceptionCode&);
     PassRefPtr<Node> importNode(Node* importedNode, ExceptionCode& ec) { return importNode(importedNode, true, ec); }
     PassRefPtr<Node> importNode(Node* importedNode, bool deep, ExceptionCode&);
     virtual PassRefPtr<Element> createElementNS(const String& namespaceURI, const String& qualifiedName, ExceptionCode&);
     PassRefPtr<Element> createElement(const QualifiedName&, bool createdByParser);
 
     bool cssStickyPositionEnabled() const;
-    bool cssRegionsEnabled() const;
     bool cssCompositingEnabled() const;
-#if ENABLE(CSS_REGIONS)
     PassRefPtr<DOMNamedFlowCollection> webkitGetNamedFlows();
-#endif
 
     NamedFlowCollection* namedFlows();
 
     bool regionBasedColumnsEnabled() const;
 
     bool cssGridLayoutEnabled() const;
 
     /**
      * Retrieve all nodes that intersect a rect in the window's document, until it is fully enclosed by
      * the boundaries of a node.
@@ skipping 1182 matching lines @@
     trackForDebugging();
 #endif
     InspectorCounters::incrementCounter(InspectorCounters::NodeCounter);
 }
 
 Node* eventTargetNodeForDocument(Document*);
 
 } // namespace WebCore
 
 #endif // Document_h