Move string tokenizer to base/strings.

base/strings/string_tokenizer.h

Index: base/strings/string_tokenizer.h
diff --git a/base/string_tokenizer.h b/base/strings/string_tokenizer.h
similarity index 97%
rename from base/string_tokenizer.h
rename to base/strings/string_tokenizer.h
index c2307a5209d1a496ce60745af11e4bf37d6f2266..791051a6b6d9638e5259ad978c8cb2d26a9cbd56 100644
--- a/base/string_tokenizer.h
+++ b/base/strings/string_tokenizer.h
@@ -2,14 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef BASE_STRING_TOKENIZER_H_
-#define BASE_STRING_TOKENIZER_H_
+#ifndef BASE_STRINGS_STRING_TOKENIZER_H_
+#define BASE_STRINGS_STRING_TOKENIZER_H_
 
 #include <algorithm>
 #include <string>
 
 #include "base/string_piece.h"
 
+namespace base {
+
 // StringTokenizerT is a simple string tokenizer class.  It works like an
 // iterator that with each step (see the Advance method) updates members that
 // refer to the next token in the input string.  The user may optionally
@@ -253,4 +255,6 @@ typedef StringTokenizerT<std::wstring, std::wstring::const_iterator>
     WStringTokenizer;
 typedef StringTokenizerT<std::string, const char*> CStringTokenizer;
 
-#endif  // BASE_STRING_TOKENIZER_H_
+}  // namespace base
+
+#endif  // BASE_STRINGS_STRING_TOKENIZER_H_