Add UMA stats for SharedWorker in SharedWorkerHost.

content/browser/shared_worker/shared_worker_host.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_BROWSER_SHARED_WORKER_SHARED_WORKER_HOST_H_
 #define CONTENT_BROWSER_SHARED_WORKER_SHARED_WORKER_HOST_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
+#include "base/time/time.h"
 #include "content/browser/shared_worker/shared_worker_message_filter.h"
 
 class GURL;
 
 namespace IPC {
 class Message;
 }
 
 namespace content {
 class SharedWorkerMessageFilter;
@@ skipping 59 matching lines @@
   // it contains a message port and sending it a valid route id.
   void RelayMessage(const IPC::Message& message,
                     SharedWorkerMessageFilter* incoming_filter);
 
   // Return a vector of all the render process/render frame IDs.
   std::vector<std::pair<int, int> > GetRenderFrameIDsForWorker();
 
   scoped_ptr<SharedWorkerInstance> instance_;
   SharedWorkerMessageFilter* container_render_filter_;
   int worker_route_id_;
+  const base::TimeTicks creation_time_;
   DISALLOW_COPY_AND_ASSIGN(SharedWorkerHost);
 };
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SHARED_WORKER_SHARED_WORKER_HOST_H_