LibWeb: Remove obsolete PlatformObject::global_object() API

Author: https://github.com/ADKaster
Commit: ade4fc1779
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/1293
Reviewed-by: https://github.com/awesomekling

Userland/Libraries/LibWeb/Bindings/PlatformObject.cpp

@@ -30,12 +30,6 @@ JS::Realm& PlatformObject::realm() const
     return shape().realm();
 }
 
-// FIXME: remove this
-HTML::Window& PlatformObject::global_object() const
-{
-    return verify_cast<HTML::Window>(realm().global_object());
-}
-
 // https://webidl.spec.whatwg.org/#dfn-named-property-visibility
 JS::ThrowCompletionOr<bool> PlatformObject::is_named_property_exposed_on_object(JS::PropertyKey const& property_key) const
 {