Fixed bug 1333 - segfault if opengl window could not get created

When the window couldn't be created, the normal window destruction process happens, which among other things, destroys the framebuffer, if any.

src/video/windows/SDL_windowsframebuffer.c

@@ -113,6 +113,11 @@ void WIN_DestroyWindowFramebuffer(_THIS, SDL_Window * window)
 {
     SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
 
+    if (!data) {
+        /* The window wasn't fully initialized */
+        return;
+    }
+
     if (data->mdc) {
         DeleteDC(data->mdc);
         data->mdc = NULL;

src/video/x11/SDL_x11framebuffer.c

@@ -193,7 +193,14 @@ void
 X11_DestroyWindowFramebuffer(_THIS, SDL_Window * window)
 {
     SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
-    Display *display = data->videodata->display;
+    Display *display;
+
+    if (!data) {
+        /* The window wasn't fully initialized */
+        return;
+    }
+
+    display = data->videodata->display;
 
     if (data->ximage) {
         XDestroyImage(data->ximage);