Fixed SDL_SetWindowFullscreen on iOS causing the window's reported dimensions and supported orientations to go out of sync with what they should be, if the device orientation was different from the screen orientation when the function call was made.

src/video/uikit/SDL_uikitappdelegate.m

@@ -242,6 +242,28 @@ SDL_IdleTimerDisabledChanged(void *userdata, const char *name, const char *oldVa
     SDL_SendAppEvent(SDL_APP_LOWMEMORY);
 }
 
+- (void)application:(UIApplication *)application didChangeStatusBarOrientation:(UIInterfaceOrientation)oldStatusBarOrientation
+{
+    UIInterfaceOrientation orientation = application.statusBarOrientation;
+    SDL_VideoDevice *_this = SDL_GetVideoDevice();
+
+    if (_this && _this->num_displays > 0) {
+        SDL_VideoDisplay *display = &_this->displays[0]; /* Main screen. */
+        SDL_DisplayMode *mode = &display->desktop_mode;
+
+        /* The desktop display mode should be kept in sync with the screen
+         * orientation so that updating a window's fullscreen state to
+         * SDL_WINDOW_FULLSCREEN_DESKTOP keeps the window dimensions in the
+         * correct orientation.
+         */
+        if (UIInterfaceOrientationIsLandscape(orientation) != (mode->w > mode->h)) {
+            int height = mode->w;
+            mode->w = mode->h;
+            mode->h = height;
+        }
+    }
+}
+
 - (void) applicationWillResignActive:(UIApplication*)application
 {
     SDL_VideoDevice *_this = SDL_GetVideoDevice();