Implement Reactive Configuration in Background Tracing

content/browser/tracing/background_tracing_manager_impl.h

 // 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.
 
 #ifndef CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_
 #define CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_
 
 #include "base/lazy_instance.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 45 matching lines @@
         void(scoped_refptr<base::RefCountedString>)> done_callback);
 
     void ReceiveTraceFinalContents(const std::string& file_contents) override;
 
    private:
     ~TraceDataEndpointWrapper() override;
 
     base::Callback<void(scoped_refptr<base::RefCountedString>)> done_callback_;
   };
 
+  class TracingTimer {
+   public:
+    TracingTimer(StartedFinalizingCallback);
+    ~TracingTimer();
+
+    void StartTimer();
+    void CancelTimer();
+
+   private:
+    void TracingTimerFired();
+
+    base::OneShotTimer<TracingTimer> tracing_timer_;
+    BackgroundTracingManager::StartedFinalizingCallback callback_;
+  };
+
   scoped_ptr<content::BackgroundTracingConfig> config_;
   scoped_refptr<TraceDataEndpointWrapper> data_endpoint_wrapper_;
   std::map<TriggerHandle, std::string> trigger_handles_;
+  scoped_ptr<TracingTimer> tracing_timer_;
   ReceiveCallback receive_callback_;
 
   bool is_gathering_;
   bool is_tracing_;
   bool requires_anonymized_data_;
   int trigger_handle_ids_;
 
   IdleCallback idle_callback_;
 
   friend struct base::DefaultLazyInstanceTraits<BackgroundTracingManagerImpl>;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundTracingManagerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_