Handle X11 events within the Win32 event loop

This unifies event handling and it allows X11 events to still be
processed even when the event loop is blocked.

src/wine-host/bridges/vst3.h

@@ -290,8 +290,6 @@ class Vst3Bridge : public HostBridge {
      */
     void run() override;
 
-    void handle_x11_events() noexcept override;
-
     /**
      * If the plugin instance has an editor, resize the wrapper window to match
      * the new size. This is called from `IPlugFrame::resizeView()` to make sure