IndexedDB: Use [Default] in IDLs to reduce overloads in implementations

Source/modules/indexeddb/IDBCursor.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 161 matching lines @@
 
     m_request->setPendingCursor(this);
     m_gotValue = false;
     m_backend->advance(count, m_request, ec);
     ASSERT(!ec);
 }
 
 void IDBCursor::continueFunction(ScriptExecutionContext* context, const ScriptValue& keyValue, ExceptionCode& ec)
 {
     DOMRequestState requestState(context);
-    RefPtr<IDBKey> key = scriptValueToIDBKey(&requestState, keyValue);
+    RefPtr<IDBKey> key = keyValue.isUndefined() ? 0 : scriptValueToIDBKey(&requestState, keyValue);
     continueFunction(key.release(), ec);
 }
 
 void IDBCursor::continueFunction(PassRefPtr<IDBKey> key, ExceptionCode& ec)
 {
     ec = 0;
     IDB_TRACE("IDBCursor::continue");
     if (key && !key->isValid()) {
         ec = IDBDatabaseException::DataError;
         return;
@@ skipping 98 matching lines @@
 PassRefPtr<IDBObjectStore> IDBCursor::effectiveObjectStore()
 {
     if (m_source->type() == IDBAny::IDBObjectStoreType)
         return m_source->idbObjectStore();
     RefPtr<IDBIndex> index = m_source->idbIndex();
     return index->objectStore();
 }
 
 IndexedDB::CursorDirection IDBCursor::stringToDirection(const String& directionString, ExceptionCode& ec)
 {
-    if (directionString == IDBCursor::directionNext())
+    if (directionString.isNull() || directionString == IDBCursor::directionNext())
         return IndexedDB::CursorNext;
     if (directionString == IDBCursor::directionNextUnique())
         return IndexedDB::CursorNextNoDuplicate;
     if (directionString == IDBCursor::directionPrev())
         return IndexedDB::CursorPrev;
     if (directionString == IDBCursor::directionPrevUnique())
         return IndexedDB::CursorPrevNoDuplicate;
 
     ec = TypeError;
     return IndexedDB::CursorNext;
@@ skipping 14 matching lines @@
     case IndexedDB::CursorPrevNoDuplicate:
         return IDBCursor::directionPrevUnique();
 
     default:
         ASSERT_NOT_REACHED();
         return IDBCursor::directionNext();
     }
 }
 
 } // namespace WebCore