Update web-platform-tests to revision b'468d01bbd84da2babf265c6af46947be68713440'

tests/wpt/web-platform-tests/js-self-profiling/resources/profiling-script.js

@@ -0,0 +1,26 @@
+(function(global) {
+  let counter = 0;
+
+  // Spins up a new profiler and performs some work in a new top-level task,
+  // calling some builtins. Returns a promise for the resulting trace.
+  const profileBuiltinsInNewTask = () => {
+    // Run profiling logic in a new task to eliminate the caller stack.
+    return new Promise(resolve => {
+      setTimeout(async () => {
+        const profiler = new Profiler({ sampleInterval: 10, maxBufferSize: 10000 });
+        for (const deadline = performance.now() + 500; performance.now() < deadline;) {
+          // Run a range of builtins to ensure they get included in the trace.
+          // Store this computation in a variable to prevent getting optimized out.
+          counter += Math.random();
+          counter += performance.now();
+        }
+        const trace = await profiler.stop();
+        resolve(trace);
+      });
+    });
+  }
+
+  global.ProfilingScript = {
+    profileBuiltinsInNewTask,
+  }
+})(window);