Make blame only check for binary mime-type on the final revision instead
of every revision.  If the final file is not binary, but was binary in the
past, blame will now run without requiring --force.

* subversion/libsvn_client/blame.c
  (struct file_rev_baton): Remove unused member.
  (check_mimetype): Remove unused function.
  (file_rev_handler): Don't check mime-type.
  (svn_client_blame5): Check final mime-type.

* subversion/svn/blame-cmd.c
  (svn_cl__blame): Add another non-existant file error.

* subversion/tests/cmdline/blame_tests.py
  (blame_binary): Adapt to test new behaviour.
  (blame_file_not_in_head, blame_multiple_targets): Tweak expected errors.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1445164 13f79535-47bb-0310-9956-ffa450edef68