Add tracing event for first connection.

examples/trace_me/trace_me_app.cc

 // Copyright 2015 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.
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/threading/thread.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 40 matching lines @@
   ~TraceMeApp() override {}
 
   // mojo:ApplicationDelegate:
   void Initialize(mojo::ApplicationImpl* app) override {
     // Allow TracingImpl to connect to the central tracing service, advertising
     // its ability to provide trace events.
     tracing_.Initialize(app);
 
     TRACE_EVENT0("trace_me", "initialized");
 
-    base::MessageLoop::current()->PostTask(FROM_HERE, base::Bind(&DoWork));
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE, base::Bind(&DoWork), kDoWorkDelay);
+  }
+
+  // mojo:ApplicationDelegate:
+  bool ConfigureIncomingConnection(
+      mojo::ApplicationConnection* connection) override {
+    TRACE_EVENT0("trace_me", "connected");
+    return true;
   }
 
  private:
   mojo::TracingImpl tracing_;
   DISALLOW_COPY_AND_ASSIGN(TraceMeApp);
 };
 
 }  // namespace examples
 
 MojoResult MojoMain(MojoHandle application_request) {
   mojo::ApplicationRunnerChromium runner(new examples::TraceMeApp);
   return runner.Run(application_request);
 }