*** DO NOT LAND *** Attempt to understand Regions complexity

Source/core/css/CSSTokenizer-in.cpp

 /*
  * Copyright (C) 2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2012 Adobe Systems Incorporated. All rights reserved.
  * Copyright (C) 2012 Intel Corporation. All rights reserved.
  *
@@ skipping 995 matching lines @@
             if (LIKELY(!hasEscape))
                 m_token = TOPRIGHTCORNER_SYM;
         }
         CASE("viewport") {
             m_token = VIEWPORT_RULE_SYM;
         }
         CASE("-internal-rule") {
             if (LIKELY(!hasEscape && m_internal))
                 m_token = INTERNAL_RULE_SYM;
         }
-        CASE("-webkit-region") {
-            if (LIKELY(!hasEscape))
-                m_token = WEBKIT_REGION_RULE_SYM;
-        }
         CASE("-internal-decls") {
             if (LIKELY(!hasEscape && m_internal))
                 m_token = INTERNAL_DECLS_SYM;
         }
         CASE("-internal-value") {
             if (LIKELY(!hasEscape && m_internal))
                 m_token = INTERNAL_VALUE_SYM;
         }
         CASE("-webkit-keyframes") {
             m_token = WEBKIT_KEYFRAMES_SYM;
@@ skipping 520 matching lines @@
     m_dataStart16[length - 1] = 0;
 
     m_is8BitSource = false;
     m_currentCharacter8 = 0;
     m_currentCharacter16 = m_dataStart16.get();
     setTokenStart<UChar>(m_currentCharacter16);
     m_lexFunc = &CSSTokenizer::realLex<UChar>;
 }
 
 } // namespace WebCore