Use a scoped_refptr in the IndexedDBCallbacks constructor.

content/browser/indexed_db/indexed_db_callbacks.cc

 // 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.
 
 #include "content/browser/indexed_db/indexed_db_callbacks.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 123 matching lines @@
       std::vector<::indexed_db::mojom::BlobInfoPtr>* blob_or_file_info);
 
  private:
   scoped_refptr<IndexedDBDispatcherHost> dispatcher_host_;
   ::indexed_db::mojom::CallbacksAssociatedPtr callbacks_;
 
   DISALLOW_COPY_AND_ASSIGN(IOThreadHelper);
 };
 
 IndexedDBCallbacks::IndexedDBCallbacks(
-    IndexedDBDispatcherHost* dispatcher_host,
+    scoped_refptr<IndexedDBDispatcherHost> dispatcher_host,
     const url::Origin& origin,
     ::indexed_db::mojom::CallbacksAssociatedPtrInfo callbacks_info)
-    : dispatcher_host_(dispatcher_host),
+    : dispatcher_host_(std::move(dispatcher_host)),
       host_transaction_id_(kNoTransaction),
       origin_(origin),
       data_loss_(blink::WebIDBDataLossNone),
       sent_blocked_(false),
       io_helper_(
           new IOThreadHelper(std::move(callbacks_info), dispatcher_host_)) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   thread_checker_.DetachFromThread();
 }
 
@@ skipping 450 matching lines @@
   IDB_TRACE("IndexedDBCallbacks::CreateAllBlobs");
   DCHECK_EQ(blob_info.size(), blob_or_file_info->size());
   if (!dispatcher_host_->blob_storage_context())
     return false;
   for (size_t i = 0; i < blob_info.size(); ++i)
     (*blob_or_file_info)[i]->uuid = CreateBlobData(blob_info[i]);
   return true;
 }
 
 }  // namespace content