Move Indexed DB from dedicated thread to task scheduler

content/browser/indexed_db/indexed_db_transaction.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_transaction.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
-#include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
 #include "base/strings/utf_string_conversions.h"
-#include "base/threading/thread_task_runner_handle.h"
+#include "base/threading/sequenced_task_runner_handle.h"
 #include "content/browser/indexed_db/indexed_db_backing_store.h"
 #include "content/browser/indexed_db/indexed_db_cursor.h"
 #include "content/browser/indexed_db/indexed_db_database.h"
 #include "content/browser/indexed_db/indexed_db_database_callbacks.h"
 #include "content/browser/indexed_db/indexed_db_tracing.h"
 #include "content/browser/indexed_db/indexed_db_transaction_coordinator.h"
 #include "third_party/WebKit/public/platform/modules/indexeddb/WebIDBDatabaseException.h"
 #include "third_party/leveldatabase/env_chromium.h"
 
 namespace content {
@@ skipping 139 matching lines @@
 
   // Not started by the coordinator yet.
   if (state_ != STARTED)
     return;
 
   // A task is already posted.
   if (should_process_queue_)
     return;
 
   should_process_queue_ = true;
-  base::ThreadTaskRunnerHandle::Get()->PostTask(
+  base::SequencedTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&IndexedDBTransaction::ProcessTaskQueue,
                             ptr_factory_.GetWeakPtr()));
 }
 
 void IndexedDBTransaction::Abort(const IndexedDBDatabaseError& error) {
   IDB_TRACE1("IndexedDBTransaction::Abort", "txn.id", id());
   DCHECK(!processing_event_queue_);
   if (state_ == FINISHED)
     return;
 
@@ skipping 61 matching lines @@
   // TransactionCoordinator has started this transaction.
   DCHECK_EQ(CREATED, state_);
   state_ = STARTED;
   diagnostics_.start_time = base::Time::Now();
 
   if (!used_) {
     if (commit_pending_) {
       // The transaction has never had requests issued against it, but the
       // front-end previously requested a commit; do the commit now, but not
       // re-entrantly as that may renter the coordinator.
-      base::ThreadTaskRunnerHandle::Get()->PostTask(
+      base::SequencedTaskRunnerHandle::Get()->PostTask(
           FROM_HERE, base::Bind(&CommitUnused, ptr_factory_.GetWeakPtr()));
     }
     return;
   }
 
   RunTasksIfStarted();
 }
 
 void IndexedDBTransaction::GrabSnapshotThenStart() {
   DCHECK(!backing_store_transaction_begun_);
@@ skipping 313 matching lines @@
 
 ::indexed_db::mojom::ObserverChangesPtr*
 IndexedDBTransaction::GetPendingChangesForConnection(int32_t connection_id) {
   auto it = connection_changes_map_.find(connection_id);
   if (it != connection_changes_map_.end())
     return &it->second;
   return nullptr;
 }
 
 }  // namespace content