ServiceWorker: Add UMA to measure execution times of onpush

content/renderer/service_worker/service_worker_script_context.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_RENDERER_SERVICE_WORKER_SERVICE_WORKER_SCRIPT_CONTEXT_H_
 #define CONTENT_RENDERER_SERVICE_WORKER_SERVICE_WORKER_SCRIPT_CONTEXT_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 98 matching lines @@
   // response.
   int current_request_id_;
 
   // Pending callbacks for GetClientDocuments().
   ClientsCallbacksMap pending_clients_callbacks_;
 
   // Capture timestamps for UMA
   std::map<int, base::TimeTicks> activate_start_timings_;
   std::map<int, base::TimeTicks> fetch_start_timings_;
   std::map<int, base::TimeTicks> install_start_timings_;
+  std::map<int, base::TimeTicks> push_start_timings_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerScriptContext);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_SERVICE_WORKER_SERVICE_WORKER_SCRIPT_CONTEXT_H_