arc: Send cryptohome ID on starting ARC instance.

chromeos/dbus/session_manager_client.h

 // Copyright (c) 2012 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 CHROMEOS_DBUS_SESSION_MANAGER_CLIENT_H_
 #define CHROMEOS_DBUS_SESSION_MANAGER_CLIENT_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 195 matching lines @@
   // Used for GetArcStartTime. Takes a boolean indicating whether the
   // operation was successful or not and the ticks of ARC start time if it
   // is successful.
   typedef base::Callback<void(bool success, base::TimeTicks ticks)>
       GetArcStartTimeCallback;
 
   // Asynchronously checks if starting the ARC instance is available.
   // The result of the operation is reported through |callback|.
   virtual void CheckArcAvailability(const ArcCallback& callback) = 0;
 
-  // Asynchronously starts the ARC instance using |socket_path| as the IPC
-  // socket for communication with the instance.  Upon completion, invokes
-  // |callback| with the result.
-  virtual void StartArcInstance(const std::string& socket_path,
+  // Asynchronously starts the ARC instance for the user whose cryptohome is
+  // located by |cryptohome_id|.  Upon completion, invokes |callback| with
+  // the result.
+  virtual void StartArcInstance(const cryptohome::Identification& cryptohome_id,

[oshima, 2016/06/01 02:10:23]

Some description about failure case would be helpful.

[Shuhei Takahashi, 2016/06/01 05:24:58]

Actually it turned out this function does not check dbus error except for
no-such-method... Please let me fix it and add comments in another change.

                                 const ArcCallback& callback) = 0;
 
   // Asynchronously stops the ARC instance.  Upon completion, invokes
   // |callback| with the result.
   virtual void StopArcInstance(const ArcCallback& callback) = 0;
 
   // Asynchronously retrieves the timestamp which ARC instance is invoked or
   // returns false if there is no ARC instance or ARC is not available.
   virtual void GetArcStartTime(const GetArcStartTimeCallback& callback) = 0;
 
   // Creates the instance.
   static SessionManagerClient* Create(DBusClientImplementationType type);
 
   ~SessionManagerClient() override;
 
  protected:
   // Create() should be used instead.
   SessionManagerClient();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SessionManagerClient);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_DBUS_SESSION_MANAGER_CLIENT_H_