Manage WebSQL callbacks with OwnPtr instead of refcounting

Source/modules/webdatabase/SQLStatementErrorCallback.h

Index: Source/modules/webdatabase/SQLStatementErrorCallback.h
diff --git a/Source/modules/webdatabase/SQLStatementErrorCallback.h b/Source/modules/webdatabase/SQLStatementErrorCallback.h
index d6ed96185784ed32c2de3c572994eb88986cacac..119cf0b797a7d520fe9b798df9cd658db1281ce1 100644
--- a/Source/modules/webdatabase/SQLStatementErrorCallback.h
+++ b/Source/modules/webdatabase/SQLStatementErrorCallback.h
@@ -29,14 +29,12 @@
 #ifndef SQLStatementErrorCallback_h
 #define SQLStatementErrorCallback_h
 
-#include "wtf/ThreadSafeRefCounted.h"
-
 namespace WebCore {
 
 class SQLTransaction;
 class SQLError;
 
-class SQLStatementErrorCallback : public ThreadSafeRefCounted<SQLStatementErrorCallback> {
+class SQLStatementErrorCallback {
 public:
     virtual ~SQLStatementErrorCallback() { }
     virtual bool handleEvent(SQLTransaction*, SQLError*) = 0;