Manage WebSQL callbacks with OwnPtr instead of refcounting

Source/modules/webdatabase/SQLTransactionSyncCallback.h

Index: Source/modules/webdatabase/SQLTransactionSyncCallback.h
diff --git a/Source/modules/webdatabase/SQLTransactionSyncCallback.h b/Source/modules/webdatabase/SQLTransactionSyncCallback.h
index b49ce4cfeb8230f46cfc16c2e5c988598ab38a16..aa8f71b25bffe617de73ff84fb0b1c647f487813 100644
--- a/Source/modules/webdatabase/SQLTransactionSyncCallback.h
+++ b/Source/modules/webdatabase/SQLTransactionSyncCallback.h
@@ -31,14 +31,12 @@
 #ifndef SQLTransactionSyncCallback_h
 #define SQLTransactionSyncCallback_h
 
-#include "wtf/RefCounted.h"
-
 namespace WebCore {
 
 class SQLTransactionSync;
 
 // Instances of this class should be created and used only on the worker's context thread.
-class SQLTransactionSyncCallback : public RefCounted<SQLTransactionSyncCallback> {
+class SQLTransactionSyncCallback {
 public:
     virtual ~SQLTransactionSyncCallback() { }
     virtual bool handleEvent(SQLTransactionSync*) = 0;