UI/AppKit: Fix wake() to use the correct run loop

wake() was using CFRunLoopGetCurrent() which returns the calling
thread's run loop. When called from an I/O thread to wake the main
thread's event loop, this would wake the wrong run loop.

Fixed by using the stored m_impl->run_loop which is captured at
construction time and refers to the event loop's owning thread.

(cherry-picked from commit da77c803c17015fa87254f85ae2da8a48b9ab071)

Ladybird/AppKit/Application/EventLoopImplementation.mm

@@ -435,7 +435,7 @@ void CFEventLoopImplementation::quit(int exit_code)
 
 void CFEventLoopImplementation::wake()
 {
-    CFRunLoopWakeUp(CFRunLoopGetCurrent());
+    CFRunLoopWakeUp(m_impl->run_loop);
 }
 
 void CFEventLoopImplementation::post_event(Core::EventReceiver* receiver, NonnullOwnPtr<Core::Event>&& event)

Meta/Lagom/Contrib/MacVideoPlayer/EventLoopImplementation.mm

@@ -436,7 +436,7 @@ void CFEventLoopImplementation::quit(int exit_code)
 
 void CFEventLoopImplementation::wake()
 {
-    CFRunLoopWakeUp(CFRunLoopGetCurrent());
+    CFRunLoopWakeUp(m_impl->run_loop);
 }
 
 void CFEventLoopImplementation::post_event(Core::EventReceiver* receiver, NonnullOwnPtr<Core::Event>&& event)