DeviceOrientation API on ChromeOS

ash/shell.cc

Index: ash/shell.cc
diff --git a/ash/shell.cc b/ash/shell.cc
index 9de2e1581e2b3cb1c284339fabaef84059a639fa..177c5834f48852ff85a8825fd299759827a8b2bc 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -120,6 +120,7 @@
 #include "ash/accelerators/spoken_feedback_toggler.h"
 #include "ui/gfx/x/x11_types.h"
 #endif  // defined(USE_X11)
+#include "ash/accelerometer/sensor_manager_delegate.h"
 #include "ash/ash_constants.h"
 #include "ash/display/display_change_observer_chromeos.h"
 #include "ash/display/display_configurator_animation.h"
@@ -816,6 +817,8 @@ Shell::~Shell() {
     display_configurator_->RemoveObserver(projecting_observer_.get());
   display_change_observer_.reset();
 
+  sensor_manager_delegate_.reset();
+
   PowerStatus::Shutdown();
 
   // Ensure that DBusThreadManager outlives this Shell.
@@ -1060,6 +1063,7 @@ void Shell::Init(const ShellInitParams& init_params) {
       new VideoActivityNotifier(video_detector_.get()));
   bluetooth_notification_controller_.reset(new BluetoothNotificationController);
   last_window_closed_logout_reminder_.reset(new LastWindowClosedLogoutReminder);
+  sensor_manager_delegate_.reset(new SensorManagerDelegate);

[timvolodine, 2014/11/07 03:27:39]

does this mean we are continuously observing sensors even when the Device
Orientation API is not used?
the general idea of Device Orientation is only to 'activate' the sensors on
demand.

[flackr, 2014/11/07 19:30:46]

Agreed, we should try to limit the lifetime of this, and eventually tell
AccelerometerReader to increase the rate to 60Hz while the API is being used.

[jonross, 2014/11/10 22:39:09]

Observing will now only occur after the delegate has been told to commence
listening

 #endif
 
   weak_display_manager_factory_.reset(