cryptohome: Make CryptohomeClient::Unmount non-blocking

chromeos/dbus/cryptohome_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_CRYPTOHOME_CLIENT_H_
 #define CHROMEOS_DBUS_CRYPTOHOME_CLIENT_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 119 matching lines @@
       const DircryptoMigrationProgessHandler& handler) = 0;
 
   // Runs the callback as soon as the service becomes available.
   virtual void WaitForServiceToBeAvailable(
       const WaitForServiceToBeAvailableCallback& callback) = 0;
 
   // Calls IsMounted method and returns true when the call succeeds.
   virtual void IsMounted(const BoolDBusMethodCallback& callback) = 0;
 
   // Calls Unmount method and returns true when the call succeeds.
-  // This method blocks until the call returns.
-  virtual bool Unmount(bool* success) = 0;
+  virtual void Unmount(const BoolDBusMethodCallback& callback) = 0;
 
   // Calls AsyncCheckKey method.  |callback| is called after the method call
   // succeeds.
   virtual void AsyncCheckKey(const cryptohome::Identification& cryptohome_id,
                              const std::string& key,
                              const AsyncMethodCallback& callback) = 0;
 
   // Calls AsyncMigrateKey method.  |callback| is called after the method call
   // succeeds.
   virtual void AsyncMigrateKey(const cryptohome::Identification& cryptohome_id,
@@ skipping 431 matching lines @@
   // Create() should be used instead.
   CryptohomeClient();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CryptohomeClient);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_DBUS_CRYPTOHOME_CLIENT_H_