Make DeviceSensorService implement MainLoop::DestructionObserver

device/sensors/device_sensor_service.cc

Index: device/sensors/device_sensor_service.cc
diff --git a/device/sensors/device_sensor_service.cc b/device/sensors/device_sensor_service.cc
index 12ffa6bb5c07cbb2f2b7495a57735d8ba4328899..08f714010d1da0c8c51f6b3a86c2f71276c823ca 100644
--- a/device/sensors/device_sensor_service.cc
+++ b/device/sensors/device_sensor_service.cc
@@ -7,6 +7,7 @@
 #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 {
@@ -16,7 +17,12 @@ DeviceSensorService::DeviceSensorService()
       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() {}
 
@@ -95,6 +101,13 @@ mojo::ScopedSharedBufferHandle DeviceSensorService::GetSharedMemoryHandle(
   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();