IDL: make optional arguments (without default) explicit sometimes

Source/modules/indexeddb/IDBFactory.h

Index: Source/modules/indexeddb/IDBFactory.h
diff --git a/Source/modules/indexeddb/IDBFactory.h b/Source/modules/indexeddb/IDBFactory.h
index a3588cdbd2ebcc06a29e01b3c4066491bdaaaf0c..dab830955b823fa1731b8b768cacfca6160bda6c 100644
--- a/Source/modules/indexeddb/IDBFactory.h
+++ b/Source/modules/indexeddb/IDBFactory.h
@@ -28,6 +28,7 @@
 #ifndef IDBFactory_h
 #define IDBFactory_h
 
+#include "bindings/core/v8/Optional.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "modules/indexeddb/IDBOpenDBRequest.h"
 #include "modules/indexeddb/IndexedDBClient.h"
@@ -51,8 +52,7 @@ public:
 
     IDBRequest* getDatabaseNames(ScriptState*, ExceptionState&);
 
-    IDBOpenDBRequest* open(ScriptState*, const String& name, ExceptionState&);
-    IDBOpenDBRequest* open(ScriptState*, const String& name, unsigned long long version, ExceptionState&);
+    IDBOpenDBRequest* open(ScriptState*, const String& name, Optional<unsigned long long> version, ExceptionState&);
     IDBOpenDBRequest* deleteDatabase(ScriptState*, const String& name, ExceptionState&);
 
     short cmp(ScriptState*, const ScriptValue& first, const ScriptValue& second, ExceptionState&);
@@ -60,8 +60,6 @@ public:
 private:
     explicit IDBFactory(IndexedDBClient*);
 
-    IDBOpenDBRequest* openInternal(ScriptState*, const String& name, int64_t version, ExceptionState&);
-
     Member<IndexedDBClient> m_permissionClient;
 };