ecore-wl2: Add event to raise when window configure is completed.

ecore-wl2: Add event to raise when window configure is completed.

Small patch to create and raise a new event letting ecore_evas know
when the window has been configured. With the addition of xdg_shell v6
support, we cannot commit a surface with an existing buffer until the
surface has been configured. This patch allows us to raise an event to
ecore_evas when the surface has been configured, so we can then attach
a buffer to it.

ref T5090

Signed-off-by: Chris Michael <cp.michael@samsung.com>