Explicitly allow early bail-out in descendant-fetching

source

@@ -87528,10 +87528,25 @@ interface <dfn>NavigatorOnLine</dfn> {
     <span data-x="fetching-scripts-perform-fetch">perform the fetch</span> steps, pass those along
     while performing the <span>internal module script graph fetching procedure</span>.</p>
 
-    <p>Wait for all of the <span>internal module script graph fetching procedure</span> invocations
-    to asynchronously complete. If any of them asynchronously complete with null, then
-    asynchronously complete this algorithm with null. Otherwise, asynchronously complete this
-    algorithm with <var>module script</var>.</p>
+    <p>These invocations of the <span>internal module script graph fetching procedure</span> should
+    be performed in parallel to each other.</p>
+
+    <p>If any invocation of the <span>internal module script graph fetching procedure</span>
+    asynchronously completes with null, optionally abort all other invocations, and then
+    asynchronously complete this algorithm with null.</p>
+
+    <p>If any invocation of the <span>internal module script graph fetching procedure</span>
+    asynchronously completes with a <span>module script</span> whose <span
+    data-x="concept-module-script-state">state</span> is "<code data-x="">errored</code>",
+    optionally abort all other invocations, and then asynchronously complete this algorithm with
+    <var>module script</var>. (The errored descendant will cause errors later in the module-fetching
+    process, but for now we treat it as a premature "success".)</p>
+
+    <p>Otherwise, wait for all of the <span>internal module script graph fetching procedure</span>
+    invocations to asynchronously complete, with <span data-x="module script">module scripts</span>
+    whose <span data-x="concept-module-script-state">states</span> are not "<code
+    data-x="">errored</code>". Then, asynchronously complete this algorithm with <var>module
+    script</var>.</p>
    </li>
   </ol>