Move Indexed DB from dedicated thread to task scheduler

content/browser/indexed_db/indexed_db_backing_store.cc

 // Copyright (c) 2013 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_backing_store.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/files/file_path.h"
@@ skipping 2581 matching lines @@
     this->last_modified_ = last_modified;
 
     delegate->Start(std::move(blob_request),
                     base::Bind(&LocalWriteClosure::Run, this));
     chained_blob_writer_->set_delegate(std::move(delegate));
   }
 
  private:
   virtual ~LocalWriteClosure() {
     // Make sure the last reference to a ChainedBlobWriter is released (and
-    // deleted) on the IDB thread since it owns a transaction which has thread
-    // affinity.
+    // deleted) on the IDB sequence since it owns a transaction which has
+    // sequence affinity.
     IndexedDBBackingStore::Transaction::ChainedBlobWriter* raw_tmp =
         chained_blob_writer_.get();
     raw_tmp->AddRef();
     chained_blob_writer_ = NULL;
     task_runner_->ReleaseSoon(FROM_HERE, raw_tmp);
   }
   friend class base::RefCountedThreadSafe<LocalWriteClosure>;
 
   // If necessary, update the timestamps on the file as a final
   // step before reporting success.
@@ skipping 1878 matching lines @@
 
 IndexedDBBackingStore::Transaction::WriteDescriptor::WriteDescriptor(
     const WriteDescriptor& other) = default;
 IndexedDBBackingStore::Transaction::WriteDescriptor::~WriteDescriptor() =
     default;
 IndexedDBBackingStore::Transaction::WriteDescriptor&
     IndexedDBBackingStore::Transaction::WriteDescriptor::
     operator=(const WriteDescriptor& other) = default;
 
 }  // namespace content