Allow to pass remount option to Mount method of cros_disks_client.

chromeos/disks/disk_mount_manager.cc

Index: chromeos/disks/disk_mount_manager.cc
diff --git a/chromeos/disks/disk_mount_manager.cc b/chromeos/disks/disk_mount_manager.cc
index c5d373743f87a8321a9ddde9fd01bf3da4978b98..493596af53281ccb40ebf5bf2c416a53e7b753bc 100644
--- a/chromeos/disks/disk_mount_manager.cc
+++ b/chromeos/disks/disk_mount_manager.cc
@@ -80,6 +80,7 @@ class DiskMountManagerImpl : public DiskMountManager {
     }
     cros_disks_client_->Mount(
         source_path, source_format, mount_label, access_mode,
+        REMOUNT_OPTION_MOUNT_NEW_DEVICE,
         // When succeeds, OnMountCompleted will be called by
         // "MountCompleted" signal instead.
         base::Bind(&base::DoNothing),