Use WebIDBKeyPath type in WebKit API, implement IndexedDBKeyPath type.

webkit/glue/idb_bindings.h

 // Copyright (c) 2011 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 <vector>
 
 #include "base/basictypes.h"
-#include "base/string16.h"
 #include "webkit/glue/webkit_glue_export.h"
 
 namespace WebKit {
 class WebIDBKey;
+class WebIDBKeyPath;
 class WebSerializedScriptValue;
 }
 
 namespace webkit_glue {
 
 // Warning: this method holds a V8 lock, it should only be called within a
 // sandbox.
-WEBKIT_GLUE_EXPORT bool IDBKeysFromValuesAndKeyPath(
+WEBKIT_GLUE_EXPORT void IDBKeysFromValuesAndKeyPath(
     const std::vector<WebKit::WebSerializedScriptValue>&
         serialized_script_values,
-    const string16& idb_key_path,
+    const WebKit::WebIDBKeyPath& idb_key_path,
     std::vector<WebKit::WebIDBKey>* values);
 
 WEBKIT_GLUE_EXPORT WebKit::WebSerializedScriptValue InjectIDBKey(
     const WebKit::WebIDBKey& key,
     const WebKit::WebSerializedScriptValue& value,
-    const string16& idb_key_path);
+    const WebKit::WebIDBKeyPath& idb_key_path);
 
 }  // namespace webkit_glue