ecore_cocoa: add on the fly resizing support.

ecore_cocoa: add on the fly resizing support.

Until now, video_resize events was received only when application returned control
to the event loop. When a window is resized dynamically a lot of video_resize
events are emitted from EcoreCocoaWindow::windowDidResize and not handled
immediatly, only when the main thread is back to the ecore main loop. This is why
there are not refreshed window areas. Call ecore_main_loop_iterate() from
windowDidResize solves the issue.

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>