[oilpan] Move IDBDatabase, IDBDatabaseCallbacks, IDBDatabaseBackendInterface and other related clas…

Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h

Index: Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h
diff --git a/Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h b/Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h
index d4f2ca69c934d71bf01ff352df07aa3ec2e452dd..2d69e62322df6081688b29fd5fb4eff7ae04e6cc 100644
--- a/Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h
+++ b/Source/modules/indexeddb/IDBDatabaseCallbacksImpl.h
@@ -36,7 +36,7 @@ class IDBDatabase;
 
 class IDBDatabaseCallbacksImpl : public IDBDatabaseCallbacks {
 public:
-    static PassRefPtr<IDBDatabaseCallbacksImpl> create();
+    static IDBDatabaseCallbacksImpl* create();
     virtual ~IDBDatabaseCallbacksImpl();
 
     // IDBDatabaseCallbacks
@@ -48,10 +48,14 @@ public:
 
     void connect(IDBDatabase*);
 
+    virtual void trace(Visitor*) const;
+
 private:
     IDBDatabaseCallbacksImpl();
 
-    // The initial IDBOpenDBRequest or final IDBDatabase maintains a RefPtr to this
+    // The initial IDBOpenDBRequest or final IDBDatabase maintains a RefPtr to this.
+    // FIXME(oilpan): We should make this a Member once we move the entire IndexedDB hierarchy to the heap.
+    // We cannot make it a Member at this point since changing a raw pointer to a Member can create a cycle.
     IDBDatabase* m_database;
 };