Eliminate mojo::Shell client lib class

mojo/services/tracing/tracing_app.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 MOJO_SERVICES_TRACING_TRACING_APP_H_
 #define MOJO_SERVICES_TRACING_TRACING_APP_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
@@ skipping 16 matching lines @@
       public TraceCollector,
       public mojo::InterfaceFactory<StartupPerformanceDataCollector>,
       public StartupPerformanceDataCollector {
  public:
   TracingApp();
   ~TracingApp() override;
 
  private:
   // mojo::ShellClient implementation.
   bool AcceptConnection(mojo::Connection* connection) override;
+  bool ShellConnectionLost() override;
 
   // mojo::InterfaceFactory<TraceCollector> implementation.
   void Create(mojo::Connection* connection,
               mojo::InterfaceRequest<TraceCollector> request) override;
 
   // mojo::InterfaceFactory<StartupPerformanceDataCollector> implementation.
   void Create(
       mojo::Connection* connection,
       mojo::InterfaceRequest<StartupPerformanceDataCollector> request) override;
 
@@ skipping 24 matching lines @@
   StartupPerformanceTimes startup_performance_times_;
   bool tracing_active_;
   mojo::String tracing_categories_;
 
   DISALLOW_COPY_AND_ASSIGN(TracingApp);
 };
 
 }  // namespace tracing
 
 #endif  // MOJO_SERVICES_TRACING_TRACING_APP_H_