Handle early ServiceRequest errors in shell::ServiceContext

services/shell/public/cpp/service.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 SERVICES_SHELL_PUBLIC_CPP_SERVICE_H_
 #define SERVICES_SHELL_PUBLIC_CPP_SERVICE_H_
 
 #include <stdint.h>
 #include <string>
 
@@ skipping 10 matching lines @@
 // The primary contract between a Service and the Service Manager, receiving
 // lifecycle notifications and connection requests.
 class Service {
  public:
   Service();
   virtual ~Service();
 
   // Called once a bidirectional connection with the Service Manager has been
   // established.
   // |identity| is the identity of the service instance.
-  // Called exactly once before any other method.
+  // Called exactly once before any calls to OnConnect().
   virtual void OnStart(const Identity& identity);
 
   // Called when a connection to this service is brokered by the Service
   // Manager. Override to expose interfaces to the remote service. Return true
   // if the connection should succeed. Return false if the connection should
   // be rejected and the underlying pipe closed. The default implementation
   // returns false.
   virtual bool OnConnect(const Identity& remote_identity,
                          InterfaceRegistry* registry);
 
   // Called when the Service Manager has stopped tracking this instance. The
   // service should use this as a signal to exit, and in fact its process may
   // be reaped shortly afterward.
   // Return true from this method to tell the ServiceContext to run its
   // connection lost closure if it has one, false to prevent it from being run.
   // The default implementation returns true.
   // When used in conjunction with ApplicationRunner, returning true here quits
   // the message loop created by ApplicationRunner, which results in the service
   // quitting.
+  // No calls to either OnStart() nor OnConnect() may be received after this is
+  // called. It is however possible for this to be called without OnStart() ever
+  // having been called.
   virtual bool OnStop();
 
   Connector* connector();
   ServiceContext* context();
   void set_context(std::unique_ptr<ServiceContext> context);
 
  private:
   std::unique_ptr<ServiceContext> context_;
 
   DISALLOW_COPY_AND_ASSIGN(Service);
 };
 
 }  // namespace shell
 
 #endif  // SERVICES_SHELL_PUBLIC_CPP_SERVICE_H_