Cleanup: Add more conversion helpers for usage.

Source/modules/device_orientation/DeviceOrientationEvent.h

Index: Source/modules/device_orientation/DeviceOrientationEvent.h
diff --git a/Source/modules/device_orientation/DeviceOrientationEvent.h b/Source/modules/device_orientation/DeviceOrientationEvent.h
index 6d27e42803917b4899ce689794bb5910dd3aa636..95954a0b1ef4075e836190ae9ed2054c5ced7bce 100644
--- a/Source/modules/device_orientation/DeviceOrientationEvent.h
+++ b/Source/modules/device_orientation/DeviceOrientationEvent.h
@@ -62,6 +62,12 @@ private:
     RefPtr<DeviceOrientationData> m_orientation;
 };
 
+inline DeviceOrientationEvent* toDeviceOrientationEvent(Event* event)
+{
+    ASSERT_WITH_SECURITY_IMPLICATION(event && event->type() == eventNames().deviceorientationEvent);

[tkent, 2013/10/08 05:24:04]

This is wrong.
 - should accept NULL event
 - checking Event::type() is incorrect because a script can set arbitrary
strings to the type.  We should use interfaceName().

[r.kasibhatla, 2013/10/08 09:40:15]

Done.

+    return static_cast<DeviceOrientationEvent*>(event);
+}
+
 } // namespace WebCore
 
 #endif // DeviceOrientationEvent_h