- provide a more meaningful error message when a file cannot be closed   because it hadn't been opened before.
- provide a more meaningful error message when a file cannot be closed
  because it hadn't been opened before.

git-svn-id: 526f3b90ad6d9b1dfe840af828070ca3d99521ac@14117 d2cacbed-c0f6-0310-851a-9dad52fc623a

johannes85/core