[Sensors] Implement bindings for AbsoluteOrientationSensor

third_party/WebKit/Source/modules/sensor/SensorProxy.h

 // Copyright 2016 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.
 
 #ifndef SensorProxy_h
 #define SensorProxy_h
 
 #include "core/dom/ExceptionCode.h"
 #include "core/page/PageVisibilityObserver.h"
 #include "device/generic_sensor/public/cpp/sensor_reading.h"
@@ skipping 18 matching lines @@
   USING_GARBAGE_COLLECTED_MIXIN(SensorProxy);
   USING_PRE_FINALIZER(SensorProxy, dispose);
   WTF_MAKE_NONCOPYABLE(SensorProxy);
 
  public:
   class Observer : public GarbageCollectedMixin {
    public:
     // Has valid 'Sensor' binding, {add, remove}Configuration()
     // methods can be called.
     virtual void onSensorInitialized() {}
-    // Platfrom sensort reading has changed.
+    // Platfrom sensor reading has changed.
+    virtual void onSensorReadingChanged() {}
+    // Observer should send 'onchange' event if needed.
+    // The 'notifySensorChanged' calls are in sync with rAF.
+    // Currently, we decide whether to send 'onchange' event based on the
+    // time elapsed from the previous notification.
+    // TODO: Reconsider this after https://github.com/w3c/sensors/issues/152
+    // is resolved.
     // |timestamp| Reference timestamp in seconds of the moment when
     // sensor reading was updated from the buffer.
     // Note: |timestamp| values are only used to calculate elapsed time
     // between shared buffer readings. These values *do not* correspond
     // to sensor reading timestamps which are obtained on platform side.
-    virtual void onSensorReadingChanged(double timestamp) {}
+    virtual void notifySensorChanged(double timestamp) {}
     // An error has occurred.
     virtual void onSensorError(ExceptionCode,
                                const String& sanitizedMessage,
                                const String& unsanitizedMessage) {}
   };
 
   ~SensorProxy();
 
   void dispose();
 
@@ skipping 93 matching lines @@
   using ReadingBuffer = device::SensorReadingSharedBuffer;
   static_assert(
       sizeof(ReadingBuffer) ==
           device::mojom::blink::SensorInitParams::kReadBufferSizeForTests,
       "Check reading buffer size for tests");
 };
 
 }  // namespace blink
 
 #endif  // SensorProxy_h