Rollup merge of rust-lang#97018 - GuillaumeGomez:fail-on-js-error, r=notriddle

Ensure that test fail if a JS error occurs

Fixes rust-lang#96902.

r? ``@notriddle``

Author: JohnTitor

src/ci/docker/host-x86_64/x86_64-gnu-tools/browser-ui-test.version

@@ -1 +1 @@
-0.9.0
+0.9.1

src/tools/rustdoc-gui/tester.js

@@ -138,7 +138,7 @@ async function main(argv) {
     try {
         // This is more convenient that setting fields one by one.
         let args = [
-            "--variable", "DOC_PATH", opts["doc_folder"],
+            "--variable", "DOC_PATH", opts["doc_folder"], "--enable-fail-on-js-error",
         ];
         if (opts["debug"]) {
             debug = true;