Oilpan: Prepare to move AbstractSQLTransaction and SQLTransaction to Oilpan heap.

Source/modules/webdatabase/SQLTransaction.h

Index: Source/modules/webdatabase/SQLTransaction.h
diff --git a/Source/modules/webdatabase/SQLTransaction.h b/Source/modules/webdatabase/SQLTransaction.h
index a315b75ffd68d43c05cae27c95deff57aafdda0d..7403150777e333ac0e92ab033253a630abcd9702 100644
--- a/Source/modules/webdatabase/SQLTransaction.h
+++ b/Source/modules/webdatabase/SQLTransaction.h
@@ -51,11 +51,12 @@ class SQLTransactionErrorCallback;
 class SQLValue;
 class VoidCallback;
 
-class SQLTransaction FINAL : public SQLTransactionStateMachine<SQLTransaction>, public AbstractSQLTransaction, public ScriptWrappable {
+class SQLTransaction FINAL : public AbstractSQLTransaction, public SQLTransactionStateMachine<SQLTransaction>, public ScriptWrappable {
 public:
-    static PassRefPtr<SQLTransaction> create(Database*, PassOwnPtr<SQLTransactionCallback>,
+    static PassRefPtrWillBeRawPtr<SQLTransaction> create(Database*, PassOwnPtr<SQLTransactionCallback>,
         PassOwnPtr<VoidCallback> successCallback, PassOwnPtr<SQLTransactionErrorCallback>,
         bool readOnly);
+    virtual void trace(Visitor*) OVERRIDE;
 
     void performPendingCallback();
 
@@ -96,7 +97,7 @@ private:
 
     SQLTransactionState nextStateForTransactionError();
 
-    RefPtrWillBeCrossThreadPersistent<Database> m_database;
+    RefPtrWillBeMember<Database> m_database;
     RefPtr<AbstractSQLTransactionBackend> m_backend;
     SQLCallbackWrapper<SQLTransactionCallback> m_callbackWrapper;
     SQLCallbackWrapper<VoidCallback> m_successCallbackWrapper;