Avoid WTF::Vector::at() and operator[] in core/html.

third_party/WebKit/Source/core/html/parser/AtomicHTMLToken.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 204 matching lines @@
 };
 
 inline void AtomicHTMLToken::initializeAttributes(
     const HTMLToken::AttributeList& attributes) {
   size_t size = attributes.size();
   if (!size)
     return;
 
   m_attributes.clear();
   m_attributes.reserveInitialCapacity(size);
-  for (size_t i = 0; i < size; ++i) {
-    const HTMLToken::Attribute& attribute = attributes[i];
+  for (const auto& attribute : attributes) {
     if (attribute.nameAsVector().isEmpty())
       continue;
 
     attribute.nameRange().checkValid();
     attribute.valueRange().checkValid();
 
     AtomicString value(attribute.value8BitIfNecessary());
     const QualifiedName& name = nameForAttribute(attribute);
     // FIXME: This is N^2 for the number of attributes.
     if (!findAttributeInVector(m_attributes, name))
       m_attributes.append(Attribute(name, value));
   }
 }
 
 }  // namespace blink
 
 #endif