Function generate_class_like_interface 

pub fn generate_class_like_interface(
    decl: &InterfaceDecl,
    ctx: &ModuleContext,
    cgctx: Option<&CodegenContext<'_>>,
    js_namespace: Option<&str>,
    scope: ScopeId,
) -> TokenStream

Generate a complete extern "C" block for a class-like interface.