Implement Reactive Configuration in Background Tracing

content/browser/tracing/background_tracing_manager_impl.h

Index: content/browser/tracing/background_tracing_manager_impl.h
diff --git a/content/browser/tracing/background_tracing_manager_impl.h b/content/browser/tracing/background_tracing_manager_impl.h
index fd1fd00ad9e4fe147d0861e37c1327448ab6b53b..5c2b88f2d8f52bb17d07352738aec15b6c595ceb 100644
--- a/content/browser/tracing/background_tracing_manager_impl.h
+++ b/content/browser/tracing/background_tracing_manager_impl.h
@@ -63,9 +63,25 @@ class BackgroundTracingManagerImpl : public content::BackgroundTracingManager {
     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_;