Report trace buffer usage as number of events, not only percentage

content/browser/devtools/protocol/tracing_handler.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_DEVTOOLS_PROTOCOL_TRACING_HANDLER_H_
 #define CONTENT_BROWSER_DEVTOOLS_PROTOCOL_TRACING_HANDLER_H_
 
 #include <set>
 #include <string>
 
@@ skipping 31 matching lines @@
       const double* buffer_usage_reporting_interval,
       scoped_refptr<DevToolsProtocol::Command> command);
 
   scoped_refptr<DevToolsProtocol::Response> End(
       scoped_refptr<DevToolsProtocol::Command> command);
   scoped_refptr<DevToolsProtocol::Response> GetCategories(
       scoped_refptr<DevToolsProtocol::Command> command);
 
  private:
   void OnRecordingEnabled(scoped_refptr<DevToolsProtocol::Command> command);
-  void OnBufferUsage(float usage);
+  void OnBufferUsage(float percent_full, size_t approximate_event_count);
 
   void OnCategoriesReceived(scoped_refptr<DevToolsProtocol::Command> command,
                             const std::set<std::string>& category_set);
 
   base::debug::TraceOptions TraceOptionsFromString(const std::string* options);
 
   void SetupTimer(double usage_reporting_interval);
 
   void DisableRecording(bool abort);
 
   scoped_ptr<base::Timer> buffer_usage_poll_timer_;
   Target target_;
   bool is_recording_;
 
   scoped_ptr<Client> client_;
   base::WeakPtrFactory<TracingHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TracingHandler);
 };
 
 }  // namespace tracing
 }  // namespace devtools
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DEVTOOLS_PROTOCOL_TRACING_HANDLER_H_