Shape Detection: Implement FaceDetection on Mac as out-of-process service

services/shape_detection/shape_detection_service.cc

+// Copyright 2017 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 "services/shape_detection/shape_detection_service.h"
+
+#include "base/macros.h"
+#include "services/service_manager/public/cpp/interface_registry.h"
+#include "services/service_manager/public/cpp/service_context.h"
+#include "services/shape_detection/face_detection_provider_impl.h"
+
+namespace shape_detection {
+
+namespace {
+
+void OnConnectionLost(std::unique_ptr<service_manager::ServiceContextRef> ref) {
+  // No-op. This merely takes ownership of |ref| so it can be destroyed when
+  // this function is invoked.
+}
+}
+
+std::unique_ptr<service_manager::Service> ShapeDetectionService::Create() {
+  return base::MakeUnique<ShapeDetectionService>();
+}
+
+ShapeDetectionService::ShapeDetectionService() = default;
+
+ShapeDetectionService::~ShapeDetectionService() = default;
+
+void ShapeDetectionService::OnStart() {
+  ref_factory_.reset(new service_manager::ServiceContextRefFactory(
+      base::Bind(&service_manager::ServiceContext::RequestQuit,
+                 base::Unretained(context()))));
+}
+
+bool ShapeDetectionService::OnConnect(
+    const service_manager::ServiceInfo& remote_info,
+    service_manager::InterfaceRegistry* registry) {
+  // Add a reference to the service and tie it to the lifetime of the
+  // InterfaceRegistry's connection.
+  std::unique_ptr<service_manager::ServiceContextRef> connection_ref =
+      ref_factory_->CreateRef();
+  registry->AddConnectionLostClosure(
+      base::Bind(&OnConnectionLost, base::Passed(&connection_ref)));
+  registry->AddInterface(base::Bind(&FaceDetectionProviderImpl::Create));
+  return true;
+}
+
+bool ShapeDetectionService::OnStop() {
+  return true;
+}
+
+}  // namespace shape_detection