Allow assertions to be enabled in Blink Release builds.

Source/core/html/parser/HTMLToken.h

 /*
  * Copyright (C) 2013 Google, Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 273 matching lines @@
         m_attributes.clear();
 
         m_data.appendVector(characters);
     }
 
     void addNewAttribute()
     {
         ASSERT(m_type == StartTag || m_type == EndTag);
         m_attributes.grow(m_attributes.size() + 1);
         m_currentAttribute = &m_attributes.last();
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
         m_currentAttribute->nameRange.start = 0;
         m_currentAttribute->nameRange.end = 0;
         m_currentAttribute->valueRange.start = 0;
         m_currentAttribute->valueRange.end = 0;
 #endif
     }
 
     void beginAttributeName(int offset)
     {
         m_currentAttribute->nameRange.start = offset - m_baseOffset;
     }
 
     void endAttributeName(int offset)
     {
         int index = offset - m_baseOffset;
         m_currentAttribute->nameRange.end = index;
         m_currentAttribute->valueRange.start = index;
         m_currentAttribute->valueRange.end = index;
     }
 
     void beginAttributeValue(int offset)
     {
         m_currentAttribute->valueRange.start = offset - m_baseOffset;
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
         m_currentAttribute->valueRange.end = 0;
 #endif
     }
 
     void endAttributeValue(int offset)
     {
         m_currentAttribute->valueRange.end = offset - m_baseOffset;
     }
 
     void appendToAttributeName(UChar character)
@@ skipping 120 matching lines @@
     // A pointer into m_attributes used during lexing.
     Attribute* m_currentAttribute;
 
     // For DOCTYPE
     OwnPtr<DoctypeData> m_doctypeData;
 };
 
 }
 
 #endif