Make DeviceSensorService implement MainLoop::DestructionObserver

services/device/device_service.h

Index: services/device/device_service.h
diff --git a/services/device/device_service.h b/services/device/device_service.h
index 69f3283e9d636f3097ed529fb3a5d4f745b8e829..de26310b40332d5911fcfa80860f3b037fa4830b 100644
--- a/services/device/device_service.h
+++ b/services/device/device_service.h
@@ -19,7 +19,8 @@ class PowerMonitorMessageBroadcaster;
 class TimeZoneMonitor;
 
 std::unique_ptr<service_manager::Service> CreateDeviceService(
-    scoped_refptr<base::SingleThreadTaskRunner> file_task_runner);
+    scoped_refptr<base::SingleThreadTaskRunner> file_task_runner,
+    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
 
 class DeviceService
     : public service_manager::Service,
@@ -27,7 +28,8 @@ class DeviceService
       public service_manager::InterfaceFactory<mojom::PowerMonitor>,
       public service_manager::InterfaceFactory<mojom::TimeZoneMonitor> {
  public:
-  DeviceService(scoped_refptr<base::SingleThreadTaskRunner> file_task_runner);
+  DeviceService(scoped_refptr<base::SingleThreadTaskRunner> file_task_runner,
+                scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
   ~DeviceService() override;
 
  private:
@@ -53,6 +55,7 @@ class DeviceService
   std::unique_ptr<device::TimeZoneMonitor> time_zone_monitor_;
 
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceService);
 };