Move two generic string split functions from sync API to their own API in base/string_split.

base/string_util.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file defines utility functions for working with strings.
 
 #ifndef BASE_STRING_UTIL_H_
 #define BASE_STRING_UTIL_H_
 
 #include <stdarg.h>   // va_list
@@ skipping 501 matching lines @@
   }
 };
 
 template<typename Char> struct CaseInsensitiveCompareASCII {
  public:
   bool operator()(Char x, Char y) const {
     return ToLowerASCII(x) == ToLowerASCII(y);
   }
 };
 
+// TODO(timsteele): Move these split string functions into their own API on
+// string_split.cc/.h files.
 //-----------------------------------------------------------------------------
 
 // Splits |str| into a vector of strings delimited by |s|. Append the results
 // into |r| as they appear. If several instances of |s| are contiguous, or if
 // |str| begins with or ends with |s|, then an empty string is inserted.
 //
 // Every substring is trimmed of any leading or trailing white space.
 void SplitString(const std::wstring& str,
                  wchar_t s,
                  std::vector<std::wstring>* r);
@@ skipping 98 matching lines @@
 #elif defined(WCHAR_T_IS_UTF32)
   typedef uint32 Unsigned;
 #endif
 };
 template<>
 struct ToUnsigned<short> {
   typedef unsigned short Unsigned;
 };
 
 #endif  // BASE_STRING_UTIL_H_