marshal.c: use ivars of marshal_dump data

* marshal.c (w_object): dump no ivars to the original by marshal_dump.
  [ruby-core:54334] [Bug #8276]
* marshal.c (r_object0): copy all ivars of marshal_dump data to the
  result object instead.  [ruby-core:51163] [Bug #7627]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40392 b2dd03c8-39d4-4d8f-98ff-823fe69b080e