gdata: Apply correct mount label when mounting archives in GData

chromeos/dbus/cros_disks_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_CROS_DISKS_CLIENT_H_
 #define CHROMEOS_DBUS_CROS_DISKS_CLIENT_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 160 matching lines @@
   // A callback to handle mount events.
   // The first argument is the event type.
   // The second argument is the device path.
   typedef base::Callback<void(MountEventType, const std::string&)
                          > MountEventHandler;
 
   virtual ~CrosDisksClient();
 
   // Calls Mount method.  |callback| is called after the method call succeeds,
   // otherwise, |error_callback| is called.
-  // When mounting an archive, the |source_format| argument passes the file
-  // extension (with the leading dot, for example ".zip"). If |source_format| is
-  // empty then the source format is auto-detected.
+  // When mounting an archive, caller may set two optional arguments:
+  // - The |source_format| argument passes the file extension (with the leading
+  //   dot, for example ".zip"). If |source_format| is empty then the source
+  //   format is auto-detected.
+  // - The |mount_label| argument passes an optional mount label to be used as
+  //   the directory name of the mount point. If |mount_label| is empty, the
+  //   mount label will be based on the |source_path|.
   virtual void Mount(const std::string& source_path,
                      const std::string& source_format,
+                     const std::string& mount_label,
                      MountType type,
                      const MountCallback& callback,
                      const ErrorCallback& error_callback) = 0;
 
   // Calls Unmount method.  |callback| is called after the method call succeeds,
   // otherwise, |error_callback| is called.
   virtual void Unmount(const std::string& device_path,
                        const UnmountCallback& callback,
                        const ErrorCallback& error_callback) = 0;
 
@@ skipping 32 matching lines @@
   // Create() should be used instead.
   CrosDisksClient();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CrosDisksClient);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_DBUS_CROS_DISKS_CLIENT_H_