LoAF: slightly improve names for event listeners

Event targets with id/src expose that attribute as part of the name.
(early feedback is that event target names are not specific enough)

Bug: 1392685
Change-Id: Ie7dd908bc148411c592eea95248c806d54d7146c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4358015
Reviewed-by: Yoav Weiss <yoavweiss@chromium.org>
Commit-Queue: Noam Rosenthal <nrosenthal@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1119859}
diff --git a/long-animation-frame/tentative/loaf-event-listener.html b/long-animation-frame/tentative/loaf-event-listener.html
index 6349c28..f866a1d 100644
--- a/long-animation-frame/tentative/loaf-event-listener.html
+++ b/long-animation-frame/tentative/loaf-event-listener.html
@@ -17,9 +17,20 @@
     img.addEventListener("load", () => {
         busy_wait();
     });
+    img.id = "image";
     document.body.appendChild(img);
     t.add_cleanup(() => img.remove());
-}, "IMG.onload");
+}, "IMG#image.onload");
+
+test_self_event_listener(t => {
+    const img = document.createElement("img");
+    img.src = "/images/green.png";
+    img.addEventListener("load", () => {
+        busy_wait();
+    });
+    document.body.appendChild(img);
+    t.add_cleanup(() => img.remove());
+}, "IMG[src=/images/green.png].onload");
 
 test_self_event_listener(t => {
     const xhr = new XMLHttpRequest();
diff --git a/long-animation-frame/tentative/loaf-first-ui-event.html b/long-animation-frame/tentative/loaf-first-ui-event.html
index f2d8dac..b30b645 100644
--- a/long-animation-frame/tentative/loaf-first-ui-event.html
+++ b/long-animation-frame/tentative/loaf-first-ui-event.html
@@ -91,7 +91,7 @@
     document.body.appendChild(img);
     t.add_cleanup(() => img.remove());
     return promise;
-  }, s => s.name === "IMG.onload", t);
+  }, s => s.name === "IMG[src=/images/green.png].onload", t);
 
   const [entry] = await entryPromise;
   assert_equals(entry.firstUIEventTimestamp, 0);