Add responsiveness_metric for timeline_based_measurement

tools/telemetry/unittest_data/interaction_enabled_page.html

Index: tools/telemetry/unittest_data/interaction_enabled_page.html
diff --git a/tools/telemetry/unittest_data/interaction_enabled_page.html b/tools/telemetry/unittest_data/interaction_enabled_page.html
index cadb1fa515537436574c5899e6aa7421cff66a36..c22dd9b8023c2b522390af47ba4497b8ec97fa0f 100644
--- a/tools/telemetry/unittest_data/interaction_enabled_page.html
+++ b/tools/telemetry/unittest_data/interaction_enabled_page.html
@@ -54,4 +54,19 @@
       This is a drawer.
     </div>
   </body>
+    <script>
+    'use strict';
+    var jankMs = 50;
+    function jankThread() {
+      console.time('Interaction.JankThreadJSRun/is_responsive');
+      var startTime = window.performance.now();
+      var currTime = startTime;
+      while (currTime - startTime < jankMs) {
+        var currTime = window.performance.now();
+      }
+      console.timeEnd('Interaction.JankThreadJSRun/is_responsive');
+    }
+    var drawer = document.getElementById('drawer');
+    drawer.addEventListener('click', jankThread);
+  </script>
 </html>