window: add window type

EGL needs to know the kind of window at run-time.

include/vlc_vout_window.h

@@ -80,6 +80,8 @@ typedef struct {
 struct vout_window_t {
     VLC_COMMON_MEMBERS
 
+    unsigned type; /**< Window handle type */
+
     /* window handle (mandatory)
      *
      * It must be filled in the open function.

src/video_output/window.c

@@ -61,6 +61,7 @@ vout_window_t *vout_window_New(vlc_object_t *obj,
     memset(&window->handle, 0, sizeof(window->handle));
     window->control = NULL;
     window->sys = NULL;
+    window->type = cfg->type;
 
     const char *type;
     switch (cfg->type) {