Find feature for tracing, at long last.

chrome/browser/resources/tracing/test_utils.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview Helper functions for use in tracing tests.
  */
 
 
 /**
@@ skipping 20 matching lines @@
           if (req.status == 200) {
             cb(req.responseText);
           } else {
             console.log('Failed to load ' + url);
           }
         }, 0);
       }
     };
     req.send(null);
   }
+
+  function newAsyncSlice(start, duration, startThread, endThread) {
+    return newAsyncSliceNamed('a', start, duration, startThread, endThread);
+  }
+
+  function newAsyncSliceNamed(name, start, duration, startThread, endThread) {
+    var s = new tracing.TimelineAsyncSlice(name, 0, start);
+    s.duration = duration;
+    s.startThread = startThread;
+    s.endThread = endThread;
+    var subSlice = new tracing.TimelineAsyncSlice(name, 0, start);
+    subSlice.duration = duration;
+    subSlice.startThread = startThread;
+    subSlice.endThread = endThread;
+    s.subSlices = [subSlice];
+    return s;
+  }
+
   return {
-    getAsync: getAsync
+    getAsync: getAsync,
+    newAsyncSlice: newAsyncSlice,
+    newAsyncSliceNamed: newAsyncSliceNamed
   };
 });