iOS: Fix the window size not being set properly when Split View is used on an iPad (bug #4586).

src/video/uikit/SDL_uikitwindow.m

@@ -69,8 +69,15 @@
 
 - (void)layoutSubviews
 {
-    /* Workaround to fix window orientation issues in iOS 8+. */
+    /* Workaround to fix window orientation issues in iOS 8. */
+    /* As of July 1 2019, I haven't been able to reproduce any orientation
+     * issues with this disabled on iOS 12. The issue this is meant to fix might
+     * only happen on iOS 8, or it might have been fixed another way with other
+     * code... This code prevents split view (iOS 9+) from working on iPads, so
+     * we want to avoid using it if possible. */
+    if (!UIKit_IsSystemVersionAtLeast(9.0)) {
         self.frame = self.screen.bounds;
+    }
     [super layoutSubviews];
 }