Use stub impl when libcros fails to load

chrome/browser/chromeos/cros/mount_library.h

 // Copyright (c) 2011 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 CHROME_BROWSER_CHROMEOS_CROS_MOUNT_LIBRARY_H_
 #define CHROME_BROWSER_CHROMEOS_CROS_MOUNT_LIBRARY_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 159 matching lines @@
     virtual void DiskChanged(MountLibraryEventType event,
                              const Disk* disk) = 0;
     virtual void DeviceChanged(MountLibraryEventType event,
                                const std::string& device_path) = 0;
     virtual void MountCompleted(MountEvent event_type,
                                 MountError error_code,
                                 const MountPointInfo& mount_info) = 0;
   };
 
   virtual ~MountLibrary() {}
+  virtual void Init() = 0;
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
   virtual const DiskMap& disks() const = 0;
   virtual const MountPointMap& mount_points() const = 0;
 
   virtual void RequestMountInfoRefresh() = 0;
   virtual void MountPath(const char* source_path,
                          MountType type,
                          const MountPathOptions& options) = 0;
   // |path| is device's mount path.
@@ skipping 20 matching lines @@
   virtual void SetLibcrosProxy(MountLibcrosProxy* proxy) {}
 
   // Factory function, creates a new instance and returns ownership.
   // For normal usage, access the singleton via CrosLibrary::Get().
   static MountLibrary* GetImpl(bool stub);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CROS_MOUNT_LIBRARY_H_