Add a guard in MojoBootstrap::OnClientLaunched()

ipc/mojo/ipc_mojo_bootstrap.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 IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
 #define IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/process/process_handle.h"
 #include "ipc/ipc_channel.h"
@@ skipping 42 matching lines @@
   int GetClientFileDescriptor() const;
   base::ScopedFD TakeClientFileDescriptor();
 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
 
  protected:
   enum State { STATE_INITIALIZED, STATE_WAITING_ACK, STATE_READY, STATE_ERROR };
 
   Delegate* delegate() const { return delegate_; }
   bool Send(Message* message);
   void Fail();
+  bool HasFailed() const;
 
   State state() const { return state_; }
   void set_state(State state) { state_ = state; }
 
  private:
   void Init(scoped_ptr<Channel> channel, Delegate* delegate);
 
   // Listener implementations
   virtual void OnBadMessageReceived(const Message& message) override;
   virtual void OnChannelError() override;
 
   scoped_ptr<Channel> channel_;
   Delegate* delegate_;
   State state_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoBootstrap);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_