Merge pull request anbox#1413 from thdaemon/fixup-window-close

platform/sdl: fixup window double-closed in SDL_WINDOWEVENT_CLOSE

Author: morphis

src/anbox/platform/sdl/window.cpp

@@ -202,9 +202,6 @@ void Window::process_event(const SDL_Event &event) {
     case SDL_WINDOWEVENT_HIDDEN:
       break;
     case SDL_WINDOWEVENT_CLOSE:
-      if (observer_)
-        observer_->window_deleted(id_);
-
       close();
       break;
     default: