Fixes three crashes

athena/system/orientation_controller.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 "athena/screen/public/screen_manager.h"
 #include "athena/system/orientation_controller.h"
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/files/file_path_watcher.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 46 matching lines @@
 }  // namespace
 
 OrientationController::OrientationController()
     : DeviceSocketListener(kSocketPath, sizeof(DeviceSensorEvent)),
       last_orientation_change_time_(0) {
   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->PostTask(
+      FROM_HERE,
+      base::Bind(&OrientationController::WatchForSocketPathOnFILE, this));
 }
 
 OrientationController::~OrientationController() {
 }
 
-void OrientationController::WatchForSocketPathOnIO() {
+void OrientationController::StopWatchingSocketPath() {

[flackr, 2014/08/21 03:24:55]

This doesn't just stop watching for the socket path, it also stops listening on
the socket (if listening). Can we call it Shutdown or something to this effect?

[oshima, 2014/08/21 15:03:41]

Done.

+  StopListening();
+  watcher_.reset();

[flackr, 2014/08/21 03:24:55]

I don't think this is safe, since this is now called before the object
destruction (on the UI thread) we could be in the middle of
WatchForSocketPathOnFILE which creates the watcher. We should schedule it to be
deleted on the FILE thread.

[oshima, 2014/08/21 15:03:41]

Thank you for the catch. Fixed. I also added shutdown_ flag to skip
OnFilePathChangedOnFILE after shutdown.

+}
+
+void OrientationController::WatchForSocketPathOnFILE() {
   CHECK(base::MessageLoopForIO::current());
   if (base::PathExists(base::FilePath(kSocketPath))) {
     ui_task_runner_->PostTask(FROM_HERE,
         base::Bind(&OrientationController::StartListening, this));
   } 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)
     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)
     return;
 
   float gravity_x = event->data[0];
   float gravity_y = event->data[1];
   gfx::Display::Rotation rotation;
   if (gravity_x < -kGravityThreshold) {
     rotation = gfx::Display::ROTATE_270;
@@ skipping 15 matching lines @@
   }
 
   last_orientation_change_time_ = event->timestamp;
   current_rotation_ = rotation;
   ui_task_runner_->PostTask(FROM_HERE,
       base::Bind(&OrientationController::RotateOnUI, this, rotation));
 }
 
 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);
 }
 
 }  // namespace athena