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

third_party/WebKit/Source/core/html/MediaFragmentURIParser.cpp

 /*
  * Copyright (C) 2011, 2012 Apple 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 132 matching lines @@
 }
 
 void MediaFragmentURIParser::parseTimeFragment() {
   DCHECK_EQ(m_timeFormat, None);
 
   if (m_fragments.isEmpty())
     parseFragments();
 
   m_timeFormat = Invalid;
 
-  for (unsigned i = 0; i < m_fragments.size(); ++i) {
-    std::pair<String, String>& fragment = m_fragments[i];
-
+  for (const auto& fragment : m_fragments) {
     DCHECK(fragment.first.is8Bit());
     DCHECK(fragment.second.is8Bit());
 
     // http://www.w3.org/2008/WebVideo/Fragments/WD-media-fragments-spec/#naming-time
     // Temporal clipping is denoted by the name t, and specified as an interval
     // with a begin time and an end time
     if (fragment.first != "t")
       continue;
 
     // http://www.w3.org/2008/WebVideo/Fragments/WD-media-fragments-spec/#npt-time
@@ skipping 145 matching lines @@
 
   if (offset < length && timeString[offset] == '.')
     fraction = collectFraction(timeString, length, offset).toDouble();
 
   time = (value1 * secondsPerHour) + (value2 * secondsPerMinute) + value3 +
          fraction;
   return true;
 }
 
 }  // namespace blink