Fixes three crashes

athena/system/orientation_controller.cc

Index: athena/system/orientation_controller.cc
diff --git a/athena/system/orientation_controller.cc b/athena/system/orientation_controller.cc
index 8996d7db1e7b601ca4b9449cc6d61c0d22b2fd33..511e0cac06fe1eca3cfae142800dd30a4945c58e 100644
--- a/athena/system/orientation_controller.cc
+++ b/athena/system/orientation_controller.cc
@@ -58,21 +58,37 @@ struct DeviceSensorEvent {
 
 OrientationController::OrientationController()
     : DeviceSocketListener(kSocketPath, sizeof(DeviceSensorEvent)),
-      last_orientation_change_time_(0) {
+      last_orientation_change_time_(0),
+      shutdown_(false) {
   CHECK(base::MessageLoopForUI::current());
   ui_task_runner_ = base::MessageLoopForUI::current()->task_runner();
 }
 
 void OrientationController::InitWith(
-    scoped_refptr<base::TaskRunner> io_task_runner) {
-  io_task_runner->PostTask(FROM_HERE, base::Bind(
-      &OrientationController::WatchForSocketPathOnIO, this));
+    scoped_refptr<base::TaskRunner> file_task_runner) {
+  file_task_runner_ = file_task_runner;
+  file_task_runner->PostTask(
+      FROM_HERE,
+      base::Bind(&OrientationController::WatchForSocketPathOnFILE, this));
 }
 
 OrientationController::~OrientationController() {
 }
 
-void OrientationController::WatchForSocketPathOnIO() {
+void OrientationController::Shutdown() {
+  CHECK(file_task_runner_);
+  StopListening();
+  file_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&OrientationController::ShutdownOnFILE, this));
+}
+
+void OrientationController::ShutdownOnFILE() {
+  shutdown_ = true;
+  watcher_.reset();
+}
+
+void OrientationController::WatchForSocketPathOnFILE() {
   CHECK(base::MessageLoopForIO::current());
   if (base::PathExists(base::FilePath(kSocketPath))) {
     ui_task_runner_->PostTask(FROM_HERE,
@@ -80,22 +96,23 @@ void OrientationController::WatchForSocketPathOnIO() {
   } else {
     watcher_.reset(new base::FilePathWatcher);
     watcher_->Watch(
-        base::FilePath(kSocketPath), false,
-        base::Bind(&OrientationController::OnFilePathChangedOnIO, this));
+        base::FilePath(kSocketPath),
+        false,
+        base::Bind(&OrientationController::OnFilePathChangedOnFILE, this));
   }
 }
 
-void OrientationController::OnFilePathChangedOnIO(const base::FilePath& path,
-                                                  bool error) {
+void OrientationController::OnFilePathChangedOnFILE(const base::FilePath& path,
+                                                    bool error) {
   watcher_.reset();
-  if (error)
+  if (error || shutdown_)

[flackr, 2014/08/21 15:07:22]

Not sure this check of shutdown_ is necessary. Since ShutdownOnFILE which sets
shutdown_ runs on the same thread and destructs the watcher I don't think this
can be called if it is shutdown_.

[oshima, 2014/08/21 16:41:00]

FilePathWatcherImpl, which really watches the file, seems to outlive
FilePathWatcher. This won't really happen in real scenario, but this is to make
sure it wont cause an problem in test or desktop.

     return;
 
   ui_task_runner_->PostTask(FROM_HERE,
       base::Bind(&OrientationController::StartListening, this));
 }
 
-void OrientationController::OnDataAvailableOnIO(const void* data) {
+void OrientationController::OnDataAvailableOnFILE(const void* data) {
   const DeviceSensorEvent* event =
       static_cast<const DeviceSensorEvent*>(data);
   if (event->type != SENSOR_ACCELEROMETER)
@@ -131,7 +148,7 @@ void OrientationController::OnDataAvailableOnIO(const void* data) {
 
 void OrientationController::RotateOnUI(gfx::Display::Rotation rotation) {
   ScreenManager* screen_manager = ScreenManager::Get();
-  // Since this is called from the IO thread, the screen manager may no longer
+  // Since this is called from the FILE thread, the screen manager may no longer
   // exist.
   if (screen_manager)
     screen_manager->SetRotation(rotation);