Certain invocations of 'svn blame -g' can trigger a client-side assertion. For
example, if you run the create-repos.sh script attached to issue #3243, and then
run 'blame -g' on the wc/trunk/foo/foo-msg.txt file created by the script but
limit the range to -r 12:14, you get:
$ svn blame wc/trunk/foo/foo-msg.txt -r 12:14 -g
subversion/libsvn_ra_neon/util.c:545: (apr_err=235000)
svn: In file 'subversion/libsvn_client/blame.c' line 486: assertion failed
(frb->last_filename == NULL)
$
libsvn_client/blame.c raises this assertion any time it sees more than one
revision from the ra-get-file-revs interface that predates the requested range
beginning (in this case, r12).
Critical SVN-3666 Assertion frb->last_filename == NULL fails in libsvn_client/blame.c
