Full-screen video's frame is incorrect in some cases

https://bugs.webkit.org/show_bug.cgi?id=245000
<radar://97807434>

Reviewed by Jer Noble.

After changing the window frame, we need to call setNeedsLayout to update the view.

* Source/WebKit/UIProcess/ios/fullscreen/WKFullScreenWindowControllerIOS.mm:
(-[WKFullScreenWindowController enterFullScreen]):

Canonical link: https://commits.webkit.org/254462@main

Source/WebKit/UIProcess/ios/fullscreen/WKFullScreenWindowControllerIOS.mm

@@ -549,6 +549,8 @@ - (void)enterFullScreen
     [_window setHidden:NO];
 #if HAVE(UIKIT_WEBKIT_INTERNALS)
     [_window setFrame:CGRectMake(0, 0, 960, 540)];
+    [_window setNeedsLayout];
+    [_window layoutIfNeeded];
 #endif
 
     _rootViewController = adoptNS([[UIViewController alloc] init]);