test_m17n_comb.rb: refine assertions

* test/ruby/test_m17n_comb.rb (test_str_scan): refine assertion
  messages.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45448 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
re.c: class name encoding

* re.c (match_inspect): preserve class name encoding by PRIsVALUE.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45449 b2dd03c8-39d4-4d8f-98ff-823fe69b080e