Ruby

• transcode.c (make_econv_exception): add several instance variables
  to exception object.
  (ecerr_source_encoding): new method:
  Encoding::ConversionUndefined#source_encoding and
  Encoding::InvalidByteSequence#source_encoding.
  (ecerr_destination_encoding): new method:
  Encoding::ConversionUndefined#destination_encoding and
  Encoding::InvalidByteSequence#destination_encoding.
  (econverr_error_char): new method:
  Encoding::ConversionUndefined#error_char.
  (econverr_error_bytes): new method:
  Encoding::ConversionUndefined#error_bytes.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@18669 b2dd03c8-39d4-4d8f-98ff-823fe69b080e