Make DeviceSensorService implement MainLoop::DestructionObserver

device/sensors/device_sensor_service.cc

 // Copyright 2014 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 "device/sensors/device_sensor_service.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
+#include "base/trace_event/trace_event.h"
 #include "device/sensors/data_fetcher_shared_memory.h"
 
 namespace device {
 
 DeviceSensorService::DeviceSensorService()
     : num_light_readers_(0),
       num_motion_readers_(0),
       num_orientation_readers_(0),
       num_orientation_absolute_readers_(0),
-      is_shutdown_(false) {}
+      is_shutdown_(false) {
+#if !defined(OS_ANDROID)

[ke.he, 2017/03/08 09:19:55]

For Non-Android platform, The strongBinding happens in IO thread, so the
DeviceSensorService should in IO thread too. For Android platform, it is in UI
thread.

+  DCHECK(base::MessageLoopForIO::IsCurrent());
+  base::MessageLoop::current()->AddDestructionObserver(this);
+#endif
+}
 
 DeviceSensorService::~DeviceSensorService() {}
 
 DeviceSensorService* DeviceSensorService::GetInstance() {
   return base::Singleton<DeviceSensorService, base::LeakySingletonTraits<
                                                   DeviceSensorService>>::get();
 }
 
 void DeviceSensorService::AddConsumer(ConsumerType consumer_type) {
   if (!ChangeNumberConsumers(consumer_type, 1))
@@ skipping 58 matching lines @@
   }
   return 0;
 }
 
 mojo::ScopedSharedBufferHandle DeviceSensorService::GetSharedMemoryHandle(
     ConsumerType consumer_type) {
   DCHECK(thread_checker_.CalledOnValidThread());
   return data_fetcher_->GetSharedMemoryHandle(consumer_type);
 }
 
+void DeviceSensorService::WillDestroyCurrentMessageLoop() {
+  DCHECK(base::MessageLoopForIO::IsCurrent());
+  base::MessageLoop::current()->RemoveDestructionObserver(this);
+  TRACE_EVENT0("shutdown", "DeviceSensorService::Subsystem:SensorService");
+  Shutdown();
+}
+
 void DeviceSensorService::Shutdown() {
   if (data_fetcher_) {
     data_fetcher_->Shutdown();
     data_fetcher_.reset();
   }
   is_shutdown_ = true;
 }
 
 void DeviceSensorService::SetDataFetcherForTesting(
     DataFetcherSharedMemory* test_data_fetcher) {
   if (data_fetcher_)
     data_fetcher_->Shutdown();
   data_fetcher_.reset(test_data_fetcher);
 }
 
 }  // namespace device