ecore_wayland: Add API ecore_wl_window_geometry_get() and use it on event handler...

ecore_wayland: Add API ecore_wl_window_geometry_get() and use it on event handler of configure.

The geometry of ecore_wl_window can be reconfigured by both of server and client.
Before, we passed its geometry as a Ecore Event in order to notify ecore_evas,
But in this case we cannot gaurantee coherence.
Thus, it would be better to give the geometry by the API on event handler.

Change-Id: Iad4ff888ab7c79ef446a083bbfe4cd362c0cb551