Add HTMLRewriter microbnechmark

bench/snippets/rewriter.mjs

@@ -0,0 +1,37 @@
+import { bench, run } from "./runner.mjs";
+
+const blob = new Blob(["<p id='foo'>Hello</p>"]);
+bench("prepend", async () => {
+  await new HTMLRewriter()
+    .on("p", {
+      element(element) {
+        element.prepend("Hello");
+      },
+    })
+    .transform(new Response(blob))
+    .text();
+});
+
+bench("append", async () => {
+  await new HTMLRewriter()
+    .on("p", {
+      element(element) {
+        element.append("Hello");
+      },
+    })
+    .transform(new Response(blob))
+    .text();
+});
+
+bench("getAttribute", async () => {
+  await new HTMLRewriter()
+    .on("p", {
+      element(element) {
+        element.getAttribute("id");
+      },
+    })
+    .transform(new Response(blob))
+    .text();
+});
+
+await run();