@ApiStatus.Experimental
  @ApiStatus.Obsolete
  public static void setOfflineByDefault(@NotNull VirtualFile file, boolean offlineByDefaultFlag) {
    ((PersistentFSImpl)PersistentFS.getInstance()).offlineByDefault(file, offlineByDefaultFlag);
  }
@ApiStatus.Experimental
  @ApiStatus.Obsolete
  public static void setOfflineByDefault(@NotNull VirtualFile file, boolean offlineByDefaultFlag)