Use a direct include of utf_string_conversions.h in android_webview/, apps/, ash/, base/.

base/string16.cc

 // Copyright (c) 2012 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.
 
 #include "base/string16.h"
 
 #if defined(WCHAR_T_IS_UTF16)
 
 #error This file should not be used on 2-byte wchar_t systems
 // If this winds up being needed on 2-byte wchar_t systems, either the
 // definitions below can be used, or the host system's wide character
 // functions like wmemcmp can be wrapped.
 
 #elif defined(WCHAR_T_IS_UTF32)
 
 #include <ostream>
 
-#include "base/utf_string_conversions.h"
+#include "base/strings/utf_string_conversions.h"
 
 namespace base {
 
 int c16memcmp(const char16* s1, const char16* s2, size_t n) {
   // We cannot call memcmp because that changes the semantics.
   while (n-- > 0) {
     if (*s1 != *s2) {
       // We cannot use (*s1 - *s2) because char16 is unsigned.
       return ((*s1 < *s2) ? -1 : 1);
     }
@@ skipping 44 matching lines @@
 
 void PrintTo(const string16& str, std::ostream* out) {
   *out << str;
 }
 
 }  // namespace base
 
 template class std::basic_string<char16, base::string16_char_traits>;
 
 #endif  // WCHAR_T_IS_UTF32