[Tizen] Device motion/orientation API

Chromium has device motion/orientation API support, but not on Tizen.
To leverage chromium's code, an xwalk::DataFetcherSharedMemory object
is created to bridge xwalk and chromium. This object acts as a sensor
event listener of xwalk and writes sensor data into chromium's shared
memory.

SPEC: http://www.w3.org/TR/orientation-event/