about:tracing support for TRACE_ASYNC_START/FINISH events.

chrome/browser/resources/tracing/linux_perf_importer.js

Index: chrome/browser/resources/tracing/linux_perf_importer.js
diff --git a/chrome/browser/resources/tracing/linux_perf_importer.js b/chrome/browser/resources/tracing/linux_perf_importer.js
index a4bf40a26a2e12100ffd6e8868d936a156a251d1..dff1bf842e45421a0be17956913bb5408f0c442c 100644
--- a/chrome/browser/resources/tracing/linux_perf_importer.js
+++ b/chrome/browser/resources/tracing/linux_perf_importer.js
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -192,6 +192,13 @@ cr.define('tracing', function() {
     },
 
     /**
+     * Called by the TimelineModel after all other importers have imported their
+     * events.
+     */
+    finalizeImport: function() {
+    },
+
+    /**
      * Builds the cpuSlices array on each thread based on our knowledge of what
      * each Cpu is doing.  This is done only for TimelineThreads that are
      * already in the model, on the assumption that not having any traced data