Use WebIDBKeyPath type in WebKit API, implement IndexedDBKeyPath type.

content/browser/in_process_webkit/indexed_db_dispatcher_host.h

 // 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.
 
 #ifndef CONTENT_BROWSER_IN_PROCESS_WEBKIT_INDEXED_DB_DISPATCHER_HOST_H_
 #define CONTENT_BROWSER_IN_PROCESS_WEBKIT_INDEXED_DB_DISPATCHER_HOST_H_
 #pragma once
 
 #include <map>
 
 #include "base/basictypes.h"
 #include "base/id_map.h"
 #include "content/public/browser/browser_message_filter.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebExceptionCode.h"
 
 class GURL;
 class IndexedDBContextImpl;
 class IndexedDBKey;
+class IndexedDBKeyPath;
 class IndexedDBKeyRange;
-class NullableString16;
 struct IndexedDBHostMsg_DatabaseCreateObjectStore_Params;
 struct IndexedDBHostMsg_FactoryDeleteDatabase_Params;
 struct IndexedDBHostMsg_FactoryGetDatabaseNames_Params;
 struct IndexedDBHostMsg_FactoryOpen_Params;
 struct IndexedDBHostMsg_IndexCount_Params;
 struct IndexedDBHostMsg_IndexOpenCursor_Params;
 struct IndexedDBHostMsg_ObjectStoreCount_Params;
 struct IndexedDBHostMsg_ObjectStoreCreateIndex_Params;
 struct IndexedDBHostMsg_ObjectStoreOpenCursor_Params;
 struct IndexedDBHostMsg_ObjectStorePut_Params;
@@ skipping 118 matching lines @@
   class IndexDispatcherHost {
    public:
     explicit IndexDispatcherHost(IndexedDBDispatcherHost* parent);
     ~IndexDispatcherHost();
 
     bool OnMessageReceived(const IPC::Message& message, bool *msg_is_ok);
     void Send(IPC::Message* message);
 
     void OnName(int32 idb_index_id, string16* name);
     void OnStoreName(int32 idb_index_id, string16* store_name);
-    void OnKeyPath(int32 idb_index_id, NullableString16* key_path);
+    void OnKeyPath(int32 idb_index_id, IndexedDBKeyPath* key_path);
     void OnUnique(int32 idb_index_id, bool* unique);
     void OnMultiEntry(int32 idb_index_id, bool* multi_entry);
     void OnOpenObjectCursor(
         const IndexedDBHostMsg_IndexOpenCursor_Params& params,
         WebKit::WebExceptionCode* ec);
     void OnOpenKeyCursor(const IndexedDBHostMsg_IndexOpenCursor_Params& params,
                          WebKit::WebExceptionCode* ec);
     void OnCount(const IndexedDBHostMsg_IndexCount_Params& params,
                  WebKit::WebExceptionCode* ec);
     void OnGetObject(int idb_index_id,
@@ skipping 28 matching lines @@
 
   class ObjectStoreDispatcherHost {
    public:
     explicit ObjectStoreDispatcherHost(IndexedDBDispatcherHost* parent);
     ~ObjectStoreDispatcherHost();
 
     bool OnMessageReceived(const IPC::Message& message, bool *msg_is_ok);
     void Send(IPC::Message* message);
 
     void OnName(int32 idb_object_store_id, string16* name);
-    void OnKeyPath(int32 idb_object_store_id, NullableString16* keyPath);
+    void OnKeyPath(int32 idb_object_store_id, IndexedDBKeyPath* keyPath);
     void OnIndexNames(int32 idb_object_store_id,
                       std::vector<string16>* index_names);
     void OnGet(int idb_object_store_id,
                int32 thread_id,
                int32 response_id,
                const IndexedDBKey& key,
                int32 transaction_id,
                WebKit::WebExceptionCode* ec);
     void OnGetByRange(int idb_object_store_id,
                       int32 thread_id,
@@ skipping 117 matching lines @@
   scoped_ptr<CursorDispatcherHost> cursor_dispatcher_host_;
   scoped_ptr<TransactionDispatcherHost> transaction_dispatcher_host_;
 
   // Used to dispatch messages to the correct view host.
   int process_id_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(IndexedDBDispatcherHost);
 };
 
 #endif  // CONTENT_BROWSER_IN_PROCESS_WEBKIT_INDEXED_DB_DISPATCHER_HOST_H_