Use WebIDBKeyPath type in WebKit API, implement IndexedDBKeyPath type.

content/browser/in_process_webkit/indexed_db_key_utility_client.h

Index: content/browser/in_process_webkit/indexed_db_key_utility_client.h
diff --git a/content/browser/in_process_webkit/indexed_db_key_utility_client.h b/content/browser/in_process_webkit/indexed_db_key_utility_client.h
index ad927e4a74521ac8ab78020d5292b2ba0b4a7d11..69efdca92284740d98c893f97b04c5a10cdc9b37 100644
--- a/content/browser/in_process_webkit/indexed_db_key_utility_client.h
+++ b/content/browser/in_process_webkit/indexed_db_key_utility_client.h
@@ -9,7 +9,6 @@
 #include <vector>
 
 #include "base/memory/ref_counted.h"
-#include "base/string16.h"
 #include "content/common/content_export.h"
 
 class IndexedDBKey;
@@ -21,6 +20,7 @@ struct DefaultLazyInstanceTraits;
 }  // namespace base
 
 namespace content {
+class IndexedDBKeyPath;
 class SerializedScriptValue;
 }
 
@@ -32,7 +32,7 @@ class IndexedDBKeyUtilityClient {
   // Synchronously obtain the |keys| from |values| for the given |key_path|.
   static void CreateIDBKeysFromSerializedValuesAndKeyPath(
       const std::vector<content::SerializedScriptValue>& values,
-      const string16& key_path,
+      const content::IndexedDBKeyPath& key_path,
       std::vector<IndexedDBKey>* keys);
 
   // Synchronously inject |key| into |value| using |key_path|. Returns the new
@@ -40,7 +40,7 @@ class IndexedDBKeyUtilityClient {
   static content::SerializedScriptValue InjectIDBKeyIntoSerializedValue(
       const IndexedDBKey& key,
       const content::SerializedScriptValue& value,
-      const string16& key_path);
+      const content::IndexedDBKeyPath& key_path);
 
   // Shut down the underlying implementation. Must be called on the IO thread.
   static void Shutdown();