Ensure SvelteElement gets correct shadow dom flag

src/compile/render-dom/index.ts

@@ -445,7 +445,7 @@ export default function dom(
 		builder.add_block(deindent`
 			class ${name} extends @SvelteElement {
 				constructor(options) {
-					super(${should_use_shadow_dom ? '' : '{ use_shadow_dom: true }'});
+					super(${should_use_shadow_dom ? '' : '{ use_shadow_dom: false }'});
 
 					${css.code && should_use_shadow_dom && `this.shadowRoot.innerHTML = \`<style>${escape(css.code, { only_escape_at_symbol: true }).replace(/\\/g, '\\\\')}${options.dev ? `\n/*# sourceMappingURL=${css.map.toUrl()} */` : ''}</style>\`;`}
 

test/js/samples/css-custom-element-no-shadow-dom/expected.js

@@ -37,7 +37,7 @@ function create_fragment(ctx) {
 
 class Component extends SvelteElement {
 	constructor(options) {
-		super({ use_shadow_dom: true });
+		super({ use_shadow_dom: false });
 
 		init(this, { target: this }, null, create_fragment, safe_not_equal, []);