- The current_pos function is supposed to return all the written bytes, not the
current position of the underlying stream.
- This caused tell() to be broken whenever the underlying stream had buffered
content.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163948 91177308-0d34-0410-b5e6-96231b3b80d8