Adds removable-drive listing for OS X.

chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc

Index: chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc
diff --git a/chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc b/chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc
index a33d47c2246c9c8bef85eef7b803c3f06e915fdb..d66f9b7f06fdad8f1ce4a410fbac233f0afd342f 100644
--- a/chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc
+++ b/chrome/browser/extensions/api/image_writer_private/removable_storage_provider_chromeos.cc
@@ -17,8 +17,9 @@ using chromeos::disks::DiskMountManager;
 // fixed disk.  In fact, some SD cards will present themselves as fixed disks
 // (see http://crbug.com/340761).  Thus we just expose all USB and SD drives.
 // static
-bool RemovableStorageProvider::PopulateDeviceList(
-    scoped_refptr<StorageDeviceList> device_list) {
+void RemovableStorageProvider::GetAllDevicesImpl(
+    const DeviceListReadyCallback& callback) {
+  scoped_refptr<StorageDeviceList> device_list(new StorageDeviceList);
   DiskMountManager* disk_mount_manager = DiskMountManager::GetInstance();
   const DiskMountManager::DiskMap& disks = disk_mount_manager->disks();
 
@@ -48,7 +49,7 @@ bool RemovableStorageProvider::PopulateDeviceList(
     }
   }
 
-  return true;
+  callback.Run(device_list, true);
 }
 
 }  // namespace extensions