Use standardized and extendable accelerometer update type.

chromeos/accelerometer/accelerometer_reader.h

Index: chromeos/accelerometer/accelerometer_reader.h
diff --git a/chromeos/accelerometer/accelerometer_reader.h b/chromeos/accelerometer/accelerometer_reader.h
index e2b85bcd4d8c4ca0768cc224b79eccb68057400e..c5e3d858f22cc5be3f188c003ab45703881b8bfe 100644
--- a/chromeos/accelerometer/accelerometer_reader.h
+++ b/chromeos/accelerometer/accelerometer_reader.h
@@ -10,6 +10,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
+#include "chromeos/accelerometer/accelerometer_types.h"
 #include "chromeos/chromeos_export.h"
 #include "ui/gfx/geometry/vector3d_f.h"
 
@@ -41,8 +42,8 @@ class CHROMEOS_EXPORT AccelerometerReader {
   // An interface to receive data from the AccelerometerReader.
   class Delegate {
    public:
-    virtual void HandleAccelerometerReading(const gfx::Vector3dF& base,
-                                            const gfx::Vector3dF& lid) = 0;
+    virtual void HandleAccelerometerUpdate(
+        const AccelerometerUpdate& update) = 0;
   };
 
   AccelerometerReader(base::TaskRunner* blocking_task_runner,
@@ -69,6 +70,9 @@ class CHROMEOS_EXPORT AccelerometerReader {
   // A weak pointer to the delegate to send accelerometer readings to.
   Delegate* delegate_;
 
+  // The last seen accelerometer data.
+  AccelerometerUpdate update_;
+
   // The accelerometer configuration.
   scoped_refptr<Configuration> configuration_;