Support WholeWord in window.find()

Source/core/editing/iterators/CharacterIterator.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov.
  *
  * 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
@@ skipping 457 matching lines @@
     }
 
     // Chinese and Japanese lack word boundary marks, and there is no clear agreement on what constitutes
     // a word, so treat the position before any CJK character as a word start.
     if (Character::isCJKIdeographOrSymbol(firstCharacter))
         return true;
 
     size_t wordBreakSearchStart = start + length;
     while (wordBreakSearchStart > start)
         wordBreakSearchStart = findNextWordFromIndex(m_buffer.data(), m_buffer.size(), wordBreakSearchStart, false /* backwards */);
-    return wordBreakSearchStart == start;
+    if (wordBreakSearchStart != start)
+        return false;
+    if (m_options & WholeWord)
+        return static_cast<int>(start + length) == findWordEndBoundary(m_buffer.data(), m_buffer.size(), wordBreakSearchStart);
+    return true;
 }
 
 inline size_t SearchBuffer::search(size_t& start)
 {
     size_t size = m_buffer.size();
     if (m_atBreak) {
         if (!size)
             return 0;
     } else {
         if (size != m_buffer.capacity())
@@ skipping 172 matching lines @@
             resultEnd = collapseTo;
             return;
         }
     }
 
     CharacterIterator computeRangeIterator(inputStart, inputEnd, iteratorFlagsForFindPlainText);
     computeRangeIterator.calculateCharacterSubrange(matchStart, matchLength, resultStart, resultEnd);
 }
 
 } // namespace blink