[Sync] Convert DTCs to be not RefCounted and NonThreadSafe.

components/sync/api/data_type_error_handler_impl.cc

Index: components/sync/api/data_type_error_handler_impl.cc
diff --git a/components/sync/api/data_type_error_handler_impl.cc b/components/sync/api/data_type_error_handler_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0cfb1f327e640dfb5c81494a5f0a13e3b6b9e75c
--- /dev/null
+++ b/components/sync/api/data_type_error_handler_impl.cc
@@ -0,0 +1,46 @@
+// Copyright 2016 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 "components/sync/api/data_type_error_handler_impl.h"
+
+#include "base/bind.h"
+#include "base/metrics/histogram.h"
+
+namespace syncer {
+
+DataTypeErrorHandlerImpl::DataTypeErrorHandlerImpl(
+    const scoped_refptr<base::SingleThreadTaskRunner>& ui_thread,
+    const base::Closure& dump_stack,
+    const ErrorCallback& sync_callback)
+    : ui_thread_(ui_thread),
+      dump_stack_(dump_stack),
+      sync_callback_(sync_callback) {}
+
+DataTypeErrorHandlerImpl::~DataTypeErrorHandlerImpl() {}
+
+void DataTypeErrorHandlerImpl::OnUnrecoverableError(const SyncError& error) {
+  if (!dump_stack_.is_null())
+    dump_stack_.Run();
+  UMA_HISTOGRAM_ENUMERATION("Sync.DataTypeRunFailures",
+                            ModelTypeToHistogramInt(error.model_type()),
+                            syncer::MODEL_TYPE_COUNT);
+  ui_thread_->PostTask(error.location(), base::Bind(sync_callback_, error));
+}
+
+syncer::SyncError DataTypeErrorHandlerImpl::CreateAndUploadError(
+    const tracked_objects::Location& location,
+    const std::string& message,
+    syncer::ModelType type) {
+  if (!dump_stack_.is_null())
+    dump_stack_.Run();
+  return syncer::SyncError(location, syncer::SyncError::DATATYPE_ERROR, message,
+                           type);
+}
+
+std::unique_ptr<DataTypeErrorHandler> DataTypeErrorHandlerImpl::Copy() const {
+  return base::MakeUnique<DataTypeErrorHandlerImpl>(ui_thread_, dump_stack_,
+                                                    sync_callback_);
+}
+
+}  // namespace syncer