Simplify & optimize StringImpl::replace(UChar, UChar)

Source/wtf/text/StringImpl.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller ( mueller@kde.org )
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 1511 matching lines @@
     if (matchLength > length())
         return false;
     unsigned startOffset = length() - matchLength;
     return equalInner(this, startOffset, matchString, matchLength, caseSensitive);
 }
 
 PassRefPtr<StringImpl> StringImpl::replace(UChar oldC, UChar newC)
 {
     if (oldC == newC)
         return this;
-    unsigned i;
-    for (i = 0; i != m_length; ++i) {
-        UChar c = is8Bit() ? characters8()[i] : characters16()[i];
-        if (c == oldC)
-            break;
-    }
-    if (i == m_length)
+
+    if (find(oldC) == kNotFound)
         return this;
 
+    unsigned i;
     if (is8Bit()) {
-        if (oldC > 0xff)
-            // Looking for a 16 bit char in an 8 bit string, we're done.
-            return this;
-
         if (newC <= 0xff) {
             LChar* data;
             LChar oldChar = static_cast<LChar>(oldC);
             LChar newChar = static_cast<LChar>(newC);
 
             RefPtr<StringImpl> newImpl = createUninitialized(m_length, data);
 
             for (i = 0; i != m_length; ++i) {
                 LChar ch = characters8()[i];
                 if (ch == oldChar)
@@ skipping 551 matching lines @@
 
 size_t StringImpl::sizeInBytes() const
 {
     size_t size = length();
     if (!is8Bit())
         size *= 2;
     return size + sizeof(*this);
 }
 
 } // namespace WTF