Merge SurfaceFactoryWayland into OzoneDisplay.

OzoneDisplay has the same interface as SurfaceFactoryWayland with some
additional APIS. This patch gets rid of SurfaceFactoryWayland and makes
OzoneDisplay as SFO implementation.
Move SurfaceOzoneImplEGL to wayland/

This patch moves SurfaceOzoneImplEGL to wayland/
Avoid unnecessary flush after swapping buffers.

We flush display after swapping buffer but this seems redundant as display
is flushed by Wayland after each swap. This patch removes the extra flush
in oz-wl side.