LibWeb: Implement HTMLStyleElement.disabled

Author: https://github.com/jamierocks
Commit: 1114bbf2f1
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/242
Reviewed-by: https://github.com/AtkinsSJ ✅

Userland/Libraries/LibWeb/HTML/HTMLStyleElement.h

@@ -23,6 +23,9 @@ public:
     virtual void inserted() override;
     virtual void removed_from(Node*) override;
 
+    bool disabled();
+    void set_disabled(bool disabled);
+
     CSS::CSSStyleSheet* sheet();
     CSS::CSSStyleSheet const* sheet() const;