Ruby

accept_nonblock: favor rb_hash_lookup2 to avoid Hash#default

• ext/socket/init.c (rsock_s_accept_nonblock): use rb_hash_lookup2
• ext/openssl/ossl_ssl.c (get_no_exception): new function
  (ossl_ssl_accept_nonblock): use get_no_exception
  (ossl_ssl_read_internal): ditto
  (ossl_ssl_write_nonblock): ditto

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49955 b2dd03c8-39d4-4d8f-98ff-823fe69b080e