Cashew: implement backend usage API

src/cashew_server.h

 // Copyright (c) 2010 The Chromium OS 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 SRC_CASHEW_SERVER_H_
 #define SRC_CASHEW_SERVER_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include <base/basictypes.h>  // NOLINT
 #include <dbus-c++/dbus.h>  // NOLINT
 
 #include "src/cashew_server_glue.h"
 #include "src/data_plan.h"
 #include "src/service.h"
-#include "src/service_manager.h"
 
 namespace cashew {
 
+class ServiceManager;
+
 // Implements Cashew D-Bus API
 class CashewServer : public org::chromium::Cashew_adaptor,
                      public DBus::IntrospectableAdaptor,
                      public DBus::ObjectAdaptor {
   public:
     CashewServer(DBus::Connection& connection,  // NOLINT
-                 const ServiceManager& service_manager);
+                 ServiceManager * const service_manager);
     virtual ~CashewServer();
 
     // Cashew D-Bus API methods
 
     // Get data plan info for a cellular service
     virtual DBusDataPlanList GetDataPlans(const std::string& service_path,
                                           DBus::Error& error);  // NOLINT
 
     // Request that a DataPlansUpdate signal be sent for a cellular service
     virtual void RequestDataPlansUpdate(const std::string& service_path,
                                         DBus::Error& error);  // NOLINT
 
     // Test method to verify that Cashew service is working
     virtual bool IsAlive(DBus::Error& error);  // NOLINT
 
     static const char* kServiceName;
     static const char* kServicePath;
 
+    // Service Manager methods
+
+    // Service Manager wants us to emit an update for a Service
+    virtual void EmitDataPlansUpdate(const Service& service);
+
   private:
-    const ServiceManager& service_manager_;
+    ServiceManager * const service_manager_;
 
-    // Emit a DataPlansUpdate signal for a service
+    // Emit a DataPlansUpdate D-Bus signal for a service
     void EmitDataPlansUpdateSignal(const Service& service);
 
     DISALLOW_COPY_AND_ASSIGN(CashewServer);
 };
 
 }  // namespace cashew
 
 #endif  // SRC_CASHEW_SERVER_H_