Use a scoped_refptr in the IndexedDBCallbacks constructor.

content/browser/indexed_db/indexed_db_callbacks.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_CALLBACKS_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_CALLBACKS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 19 matching lines @@
 class IndexedDBDatabase;
 struct IndexedDBDataLossInfo;
 struct IndexedDBDatabaseMetadata;
 struct IndexedDBReturnValue;
 struct IndexedDBValue;
 
 class CONTENT_EXPORT IndexedDBCallbacks
     : public base::RefCounted<IndexedDBCallbacks> {
  public:
   IndexedDBCallbacks(
-      IndexedDBDispatcherHost* dispatcher_host,
+      scoped_refptr<IndexedDBDispatcherHost> dispatcher_host,

[cmumford, 2016/11/22 21:40:10]

This change looks good, but can you also change the other two constructors to
preserve symmetry?

[Reilly Grant (use Gerrit), 2016/11/22 21:54:53]

What other constructors? After landing my last Mojo conversion patch this should
be the only constructor.

[cmumford, 2016/11/28 21:57:28]

Nevermind. resolved in offline discussion.

       const url::Origin& origin,
       ::indexed_db::mojom::CallbacksAssociatedPtrInfo callbacks_info);
 
   virtual void OnError(const IndexedDBDatabaseError& error);
 
   // IndexedDBFactory::GetDatabaseNames
   virtual void OnSuccess(const std::vector<base::string16>& string);
 
   // IndexedDBFactory::Open / DeleteDatabase
   virtual void OnBlocked(int64_t existing_version);
@@ skipping 80 matching lines @@
 
   std::unique_ptr<IOThreadHelper, BrowserThread::DeleteOnIOThread> io_helper_;
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(IndexedDBCallbacks);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_CALLBACKS_H_